IMPROVEMENTS IN WEIGHING MACHINES, AND IN APPARATUS FOR REDUCING TO WEIGHT, PART OF WHICH IMPROVEMENTS ARE APPLICABLE FOR FEEDING BLANKS TO COINING PRESSES AND TO OTHER MACHINES
Year: 1866

page_text: LETTERS PATENT to James Murdoch Napier, of York Road, Lambeth,
in the County of Surrey, for the Invention of "IMPROVEMENTS IN WEIGHING
MACHINES, AND IN APPARATUS FOR REDUCING TO WEIGHT, PART OF WHICH
IMPROVEMENTS ARE APPLICABLE FOR FEEDING BLANKS TO COINING PRESSES AND
TO OTHER MACHINES."
Sealed the 9th July 1866, and dated the 12th January 1866.
PROVISIONAL SPECIFICATION left by the said James Murdoch Napier
at the Office of the Commissioners of Patents, with his Petition, on
the 12th January 1866.
I, JAMES MURDOCH NAPIER, of York Road, Lambeth, in the County of
Surrey, do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN WEIGHING MACHINES, AND IN APPARATUS FOR REDUCING TO WEIGHT, PART OF
WHICH IMPROVEMENTS ARE APPLICABLE FOR FEEDING BLANKS TO COINING PRESSES
AND TO OTHER MACHINES," to be as follows:-
This Invention has for its object improvements in automaton weighing
machines for weighing and classifying according to weight, and for indicating
the weight of coin and coin blanks (including an improved mode of feeding
such machines with coin and coin blanks, which mode of feeding is also

page_text: applicable for feeding blanks to coining presses and other machines), and
improvements in weighing machines for assay purposes, and also in other
weighing machines, as well as in apparatus for reducing too heavy coin blanks
to weight, and in apparatus for reducing assay pieces to a desired weight.
Automaton weighing machines are in use at the Bank of England, at the
Royal Mint, and in other places, and the present mode of feeding them is by
placing from time to time a number of coins or coin blanks (which I shall
indifferently term "pieces" hereafter), as the case may be, ranged in single
line in an open inclined feeding duct down which they gravitate as the lowest
"piece" is successively removed by the feeding slide of the machine to be
weighed. To avoid the trouble and attention required to keep the feeding
duct supplied by hand I provide a hollow vessel, which I will call the feeding
vessel, into which the "pieces" may be put in the mass without arrangement.
This vessel is by self-acting means gradually emptied of its contents, so as to
keep replenished an inclined feeding duct which directs the "pieces" to the
feeding slide of the machine, the flow of the "pieces" from the feeding vessel
is subject to regulation by the weight of the "pieces" present in the feeding
duct. I prefer to place the feeding vessel in connection with mechanism
which will impart to it two movements, by one of which the bottom of the
vessel is raised as in the emptying of a bucket, and by the other the vessel is
made to revolve (to use the same subject for illustration) in the direction of
the hoops on the bucket. By these combined movements, properly timed, the
feeding vessel may be gradually emptied of its contents, which as they come
from the feeding vessel fall on to an incline formed so as to direct them into
an inclined feeding duct, which is closed or partially closed by a fixed or
moveable cover, so as to keep the "pieces" in one regular row. The upper
end of the feeding duct is supported by a spring, balance weight, weighted
lever, or other means in such manner that when the feeding vessel supplies
the " 'pieces too fast for the speed at which they are taken away by the
feeding slide of the machine, and they accumulate in the feeding duct, their
weight will depress its upper end. This action I make available through
suitably arranged connections to check or entirely arrest one or both move-
ments of the feeding vessel, and consequently the supply of "pieces" to the
feeding duct. When the number of "pieces" in the feeding duct gets low
the reverse action takes place, and the mechanism which gives motion to the
feeding vessel is put in action for the supply of more "pieces."
و"
This part of my Invention it will be easily understood is also applicable for
feeding blanks to coining presses and to other machines to which such
"pieces are required to be supplied at regular rates of feeding. When two

page_text: or more automaton weighing machines are placed conveniently near together
I concentrate their feeding ducts towards one position to facilitate the supply
of "pieces" to them when effected by an attendant, and when each machine is
supplied by a self-acting feeding. vessel I group these vessels together for
convenience in charging them with "pieces." In concentrating the feeding
ducts of several machines towards one position I so form and arrange them
as to permit an easy flow of the "pieces." When two or more automaton
weighing machines which are placed near together are to be engaged in
weighing a quantity of "pieces," with which they may be supplied without
distinction, I provide an inclined general feeding channel, and keep it supplied
with "pieces" either by an attendant or by a self-acting feeding apparatus
from a general feeding vessel. The pieces pass down the general feeding
channel by their gravity, and are received into the feeding ducts of each
machine. These ducts may be arranged so that when they are sufficiently
furnished the weight of the "pieces" will operate to arrest the supply from
the general feeding channel. Instead of an inclined general feeding channel
down which the "pieces" pass by their own weight a horizontal or conveniently
inclined general feeding channel may be used, the "pieces" being moved
along it by a propelling brush, or when preferred I employ a carrying band
or bands to keep the ducts of the several machines supplied, which band or
bands may be furnished with "pieces" either by an attendant or by a self-
acting apparatus from a general feeding vessel. I also facilitate the collection
of the "pieces" after they have been weighed and classified by automaton
weighing machines (when two or more engaged in the production of similar
results are placed conveniently near together) by means of inclined general
receiving channels, each of which receives all pieces of one class from the
several machines, and conducts them to a general receptacle for the class.
Instead of giving an inclination to the general receiving channels in order that
the "pieces" may pass down by their own weight, these channels may be
placed horizontally, or at any convenient angle, and a brush propelling
apparatus may be used to move the "pieces" along; or if preferred I employ
a carrying band or bands for collecting each class of "pieces" from the several
machines and delivering them into general class receptacles. I also employ
carrying bands generally in connection with automaton weighing machines for
removing the "pieces" from place to place, such carrying bands to be arranged
with due regard to convenience according to the locality and to the mode in
which the operations of the weighing department are to be conducted.
In further description of my improvements in automaton weighing machines I
would remark that the present mode of pushing the "piece" on to the weighing

page_text: plate by the feeding slide wears away the surface of the plate and disturbs
the adjustment of the machine, and when the "pieces" are bent or have
ragged edges they are liable to catch against the weighing plate. To avoid
these inconveniences I arrange a feeding slide to push the piece into a
position where it is supported immediately over the weighing plate, and
near to but not touching it. I then cause it to descend and rest upon the
weighing plate by another movement. After the "piece" has been weighed
it is raised again from the weighing plate before being pushed away. In-
stead of the present long vibrating single channel distributor tube which
receives the " pieces" directly from the weighing plate into its upper and
larger end and distributes them out of its lower and narrow end according to
their class into one or other of the openings leading to their respective
receptacles, I substitute a fixed mouth-piece to receive the "pieces," after
weighing, which diminishes in size at its lower part until the opening is only
sufficient to allow the "pieces" to pass freely edgewise. Below this mouth-
piece I place a distributor tube divided into as many channels or compart-
ments as the "pieces" are to be distributed into classes; this tube vibrates
upon an axis placed at or near to its lower end, so that the opening to one or
other of its channels or compartments becomes opposed to the opening at the
lower end of the fixed mouth-piece, according to the class the "piece" which
has been last weighed is to occupy. The "piece" passes down the channel
in the distributor tube and is so directed into the receptacle provided for
pieces" of its weight. By means of my improved fixed mouth-piece and
distributor tube I am enabled to expedite the action of the machine, as the
fixed mouth-piece can be made much shorter than the present distributor
tube, the action of which is limited, owing to the time required for the
"pieces" to pass out of it into the channels connected with the receptacles
for the different classes of "pieces."
66
In order further to expedite the working of the Mint automaton weighing
machine I replace the three-step stop piece now used in connection with the
distributor tube by a stop piece of different form, the middle stop, or that
which serves to direct the medium "pieces" being made to project more than.
the stops above and below it, which serve to direct the too light and too heavy
"pieces." This middle stop is provided with a notch along its thickness,
into which the knife end of the retaining stop lever which is in connection
with the testing lever may enter. I adjust my improved stop piece in position
so that when the "piece" is medium weight the distributor tube as it vibrates
towards the end of the stop lever will be arrested when over the opening for
the medium "pieces" by the knife edge falling into the notch referred to.

page_text: When the piece is found to be too heavy or too light the medium stop
will miss the end of the stop lever, which will be either above or below it
according to the weight of the "piece," and the distributor tube will therefore
continue its forward vibration until arrested by the too light or too heavy stop
as the case may be. It is immaterial which of these stops is placed next in
prominence, but should the too heavy stop be so placed, the opening for the
too heavy pieces" will be placed next, and that for the too light "pieces"
last. Instead of providing a stop-piece to come against the end of the stop
lever to direct the distributor tube over the last channel the distributor tube
may be allowed to come to rest against a conveniently situated fixed stop.
"
I have explained my improved stop piece in connection with the distributor
tube now in use; when it is used along with my improved distributor tube
the channels in the tube must be placed in suitable rotation. I employ a
regulating screw for the purpose of adjusting the stop piece to its proper
position, as it is more convenient than the present mode and adinits of
greater accuracy in the adjustment. In order conveniently to regulate the
range of action of the stop lever in relation to that of the testing lever (which
levers at present are arranged to vibrate together upon the same centre) I
mount them upon separate centres and connect them together so that the
testing lever in performing its vibrations will suitably actuate the stop lever.
In automaton weighing machines arranged for using remedy weights I attach
the double stirrup piece (which raises the remedy weight) to the end of the
pendant and central with it, and the rest for the remedy weight I also place
central with and below the pendant so that when the remedy weight is put
into its rest it traverses the vertical line of the pendant. In order to attain
to a very exact and convenient adjustment of the remedy weight to height I
provide a fine screw placed directly under the centre of the rest for the
remedy weight by which it can be raised and lowered at pleasure, and I
prefer to arrange this screw so that it may be accessible by passing the hand
underneath the table of the machine, as in so doing the hand will not obstruct
the view; and for the purpose of causing the remedy weight to be more
clearly seen when in position and more easily got at, I deprive the double
stirrup piece of its two outer tie bars, so that the remedy weight can be taken
out and replaced in its rest with much greater facility than at present.
In automaton weighing machines which are to indicate the weight of each
blank, as well as in those automaton weighing machines which are to be used
in combination with my apparatus for reducing the too heavy blanks to a
given weight I dispense with "remedy weights," and I alter the construction
of the weighing beam, which as at present made has its centre of gravity and

page_text: " with a
centre of action coincident, or nearly so, that it may respond the more sensibly
to a very small preponderating weight, and I place the centre of gravity lower
than usual by the addition of an adjustable or fixed weight to the under side
of the beam, so regulated in quantity and position that a given amount of
vibration will represent the preponderance of a given weight upon the end of
the beam. Thus in weighing a sovereign blank or other "piece
beam of this description, if a counterpoise is used of the exact standard, and
the "piece" weighed be heavier than standard, by one grain, let us suppose,
that excess of weight causes the end of the beam upon which it is placed to
dipth of an inch; the reverse will take place when the "piece" is one
grain lighter than standard, and by accurately measuring the rise or fall of
the beam the weight of the "piece" ("plus" or "minus" the standard) may
be ascertained. To measure the vibration of the beam produced by the
plus" or "minus" weight, as the case may be, of the "piece" weighed I
cause the beam to be retained in its position by a gripping action as soon as
the weighing is completed, and while it is so retained I ascertain the amount
of vibration by a testing lever arranged as in the machines now in use, or to
ensure greater accuracy I connect a slide to the end of the lever and apply it
against the bottom of the weighing plate pendant, or to the top or bottom of
the counterpoise pendant. To exhibit the weight of the piece I place an
indicator in connection with the testing lever to be actuated by it. To
reduce too heavy blanks to a given weight I combine my improved apparatus
for this purpose, to which I shall presently refer, with the automaton weighing
machine, and I make the testing lever to influence the reducing apparatus
through the medium of suitable connections in proportion to the quantity of
metal which is to be taken off each "piece" to reduce them to the proper
weight.
86
In automaton weighing machines which are combined with my reducing
apparatus instead of using a distributor tube to separate the "pieces" into
classes they pass down a fixed tube or guide after being weighed into the
reducing apparatus, which receives each in succession, and cuts off the
required quantity, and when thus reduced to the given weight they pass into
a general receptacle. When it is desired to reduce the too heavy pieces
so as to bring them within certain limits of the standard weight, light or
heavy, I arrange the automaton weighing machine to divide them into four or
more classes of weight, as may be found sufficient, by means of a distributor
tube containing the necessary number of channels and stops to suit, and I
provide additional "remedy weights" placed so as to be acted upon in
succession as the beam vibrates; or if preferred iny arrangement of a

page_text: low centre of gravity beam above explained may be used instead of
"remedy weights." When the too heavy blank has thus been weighed
and distributed into its proper channel it is directed into a reducing
apparatus, the cutting tool of which is adjusted to take off a fixed
quantity, and in connection with every channel into which the "pieces "
are distributed I place a similar apparatus, each of which is adjusted
to cut off a different quantity of metal according to the class of " piece "
it has to reduce. Thus, for illustration, let us suppose the limit allowed
on each side of standard to be of a grain, the too heavy "pieces" will
then be more than of a grain beavier than standard, and if we further
suppose the greatest excess of weight to be 1 grains above standard, the
reducing apparatus which is to treat the heaviest "pieces" should deduct 1
grains, and if the "pieces "are divided into five classes, the second apparatus
should deduct 1 grain, the third grain, the fourth grain, and the fifth
brought within the
grain, and thus the whole of the "pieces" may be
limits of the remedy although not to the same weight. In both the reducing
apparatuses to which I have referred (namely, that for adjusting to one
weight all the too heavy blanks by taking from each a quantity varying
according to the weight of the blank, and that other which takes off the
same quantity without variation from each blank which it treats,) I employ
a single cutting tool such as suits for turning or planing, and I place in
front of the cutting edge, or on either side of it, a burnisher stop which can
be adjusted in its relation to the edge of the tool so as to regulate the depth
of the cut. This burnisher stop and the tool are kept up to their work by
an elastic force, and while the burnisher stop rubs against the surface of the
blank under reduction the tool enters the metal to the required depth and
takes off an equal cut. In reducing coin blanks I prefer to take the metal
from the face of the "piece" by a circular cut, and in the apparatus which
deducts a varying quantity I employ self-acting means either to advance and
retire the tool (so as to allow it to take a longer or shorter cut according to
the quantity to be deducted from the blank under treatment), or to increase
or diminish the distance of the tool from the centre of the "piece," and
consequently the size of the circle cut from its face.
In the other reducing
apparatus the tool is adjusted in position so as to take off a certain fixed
quantity, and tools of various widths will be found convenient for the same
purpose. Instead of connecting the reducing apparatuses to work in con-
junction with the weighing machine they may, when preferred, be placed
separate, in which case the reducing apparatus which takes off a varying
quantity must be set by band for every blank according to its weight, as

page_text: indicated by the weighing machine, and to facilitate such setting I provide
a suitable indicator. The other reducing apparatuses which take off a fixed
quantity will be supplied with classified blanks from the receptacles of the
weighing machine.
For the purpose of weighing assay pieces, and reducing them to weight,
as well as for weighing the resulting metal to constitute assays, I employ
a weighing machine and reducing apparatus, which I arrange to work more
or less automatically as may be desired. I prefer to construct my improved
assay weighing machines with surface weighing plate and pendants instead
of the usual hanging scales. The assay piece or the resulting metal of the
assay, as the case may be, is placed upon the weighing plate and removed
from it by suitable apparatus working in concert with the other movements
of the machine, or independently actuated by the attendant, as may be
preferred. I use a weighing beam weighted on the under side with an
adjustable or fixed weight such as I have already referred to as applied to
my improved automaton machines for indicating the weight of coin and
coin blanks. When the counterpoise used represents the required weight to
which the assay piece is to be reduced the amount of deflection or dip of
the beam will indicate the excess of weight in the piece, and to measure the
deflection with accuracy, and display the result to the attendant, and com-
municate the same when required to the reducing apparatus, I employ a
fixing or gripping motion and testing and indicating apparatus nearly
analogous to those which I use in my improved automaton coin and coin
blank weighing machines. Instead of using a counterpoise equal to the
required weight of the assay piece, and allowing the deflection only of the
beam at the weighing end to indicate the excess beyond that weight, the
counterpoise may be increased to represent in addition to the required
weight of the piece the average excess of weight in a number of pieces.
The beam will then vibrate upwards at its weighing end when the piece
is lighter than the average, and downwards when it is heavier. By this
method the weighing may be performed more rapidly as the vibration of
the beam from its position of rest can be conveniently diminished. To
bring the beam to its position of rest, and to relieve for weighing a
rising and falling horizontal bar similar to that at present employed in the
coin and coin blank automaton weighing machines may be used to act upon
the pendants, but I prefer to employ for the purpose a vertical gripping action
applied against a horizontal bar attached to or forming part of either one of
the pendants, or otherwise connected to the weighing beam, the grippers being
arranged to open and close in the direction in which the bar against which

page_text: they act vibrates, and they are capable of adjustment to height so that when
they come together upon the bar the beam will be in its proper position of
rest, and they are opened and closed at the desired speed and at the proper
times by a suitable cam motion. Instead of acting to grip a bar they may, if
preferred, be arranged to act in the reverse sense against the top and bottom
of a suitably formed opening. This mode of setting the beam to position, and
releasing it for weighing, is also applicable to coin and coin blank automaton
weighing machines and to other weighing machines. In automaton coin
and coin blank weighing machines, as well as in assay weighing machines,
when it is desired to obtain a quick and clear release of the beam for
weighing I apply grippers for releasing the beam for weighing, which are
arranged to open and close horizontally or at right angles to the direction in
which the portion against which they act vibrates when the beam is released
for weighing. When grippers so arranged are employed for releasing the
beam for weighing the setting of the beam back to its position of rest may
be accomplished by either of the methods just described, or by other suitable
nieans. In weighing the resulting metal of the assay by means of my
improved assay weighing machine just described it will be desirable as
recommended in the case of assay pieces to use a counterpoise of such a weight
as will be about equal to the average load, so that the beam may vibrate
upwards as well as downwards at the weighing end and indicate the "plus">
or "minus" weight, as the case may be.
In this process of weighing the arrangements which I make for connecting
my assay weighing machines when used for weighing assay pieces with the
reducing apparatus are not required. I employ the usual means for preparing
the assay pieces by reducing the metal to a convenient thickness, and afterwards
cutting out with a punch a disc of suitable dimensions, but in order that I may
be able to effect the exact reduction of these discs to a given weight by my
reducing apparatus, notwithstanding their varying specific gravities, I employ
more than the usual care to ensure that in assays of gold all the discs or assay
pieces shall be precisely of one thickness and of one diameter, and that for
silver assays the discs (which are usually made larger than in the assays of
gold) shall also be as nearly as possible of one diameter and one thickness.
It will be understood that when assay pieces of equal or nearly equal volume
are weighed in my assay weighing machine the indicated excess in each piece
beyond that weight to which it is to be reduced will be in proportion or nearly
so to the specific gravity of the piece. I therefore arrange my reducing
apparatus for assay pieces to deduct proportionally less metal per grain or
part of a grain of excess when the excess in the weight of the piece is large,

page_text: and proportionally more when the excess in weight is small, so as to bring
the pieces all to the same weight. This I accomplish when the reducing
apparatus is to work with the weighing machine (to be influenced by it to
deduct the proper quantities), by placing in connection with the testing lever
a suitably formed incline to regulate and proportion the action which is com-
municated to the reducing apparatus, so that it will be increased per unit of
weight when the quantity to be deducted is large, and decreased in the same
relation when the quantity to be deducted is small. I also use a spirally
formed plane for this purpose arranged to act directly on the beam or on one
of the pendants, or indirectly through the medium of a testing lever. When
the reducing apparatus is used separate from the weighing machine the weight
of the piece must be noted by the attendant, who will also set the reducing
apparatus to take off the proper quantity by means of an indicator provided
for the purpose. The assay pieces may be reduced to weight in the manner
I have explained for reducing coin blanks to one weight and with the same
description of cutting tool and burnisher stop, but as the quantity to be
deducted in the case of assay pieces is often much larger in proportion to the
size of the piece, and as it is also of little consequence from what part of the
piece it is taken, I prefer to employ a punch cutter to cut into the piece from
the edge. The piece takes its position by coming against a stop slide which
is adjusted in relation to the cutter punch according to the weight of the piece
(either by its connection with the weighing machine or when separate from it
by the attendant, who sets the reducing apparatus by the indicator), so that
the piece comes more or less under the cutter punch, and a notch is cut in it
beginning at its circumference and arriving more or less near to its centre
according to the weight of the piece. When it is found difficult to attain to
a result sufficiently accurate in one process of reduction I arrange the first
reducing apparatus so as to leave a small excess of weight in each piece, and
I reweigh them to ascertain the exact amount of such excess, and again treat
them in a reducing apparatus suitably adjusted to deduct the excess, and
provided with a fine tool for the purpose. In making this last reduction the
specific gravity of each piece, as indicated by its first weight or the quantity
of excess of weight first deducted from it, may be taken into account and
allowed for in the adjustment of the second and final reducing apparatus, and
for this purpose I provide additional means of adjustment to correct and
proportion in accordance with the specific gravity of the piece the quantity in
volume to be deducted from it, in order to secure the exact reduction of the
ascertained excess of weight.
My improved arrangement of a weighing beam weighted on the under side

page_text: with an adjustable or fixed weight (so that the amount of its vibration will
represent the difference in weight between the counterpoise and the load
weighed,) combined with a fixing or gripping apparatus for retaining the beam
in its position after weighing, and a measuring or testing apparatus for
ascertaining the exact quantity of vibration while the beam is so retained by
the grippers with an indicator attached for exhibiting that quantity to the
weigher is applicable to other weighing machines, and more especially for
checking quantities which have been already weighed, and for which the
proper counterpoise can be readily selected. In other cases a counterpoise
sufficiently approximating to the weight of the load may be found by trial.
This mode of weighing enables me to dispense with the use of small weights,
and to obtain very accurate results with great facility. When I employ a
vertical gripper releasing action, such as I have explained in connection with
my improved automaton and assay weighing machines, for finally releasing the
weighing beams of such machines as are used for weighing bullion and other
Leavy weights, I arrange it to act in concert with any other ordinary con-
venient mode of releasing the beam, and I construct the gripper releasing
action to effect the release of the beam only when the load is within a given
limit of the weight of the counterpoise. In bullion weighing machines which
are furnished with grippers opening horizontally to release the beam finally
when the load and the counterpoise are nearly equal I place the grippers upon
an axis so that they will vibrate with the beam when the difference between
the load and the counterpoise exceeds a given limit. For convenience in
applying power to automaton weighing machines I place a driving shaft below
the level of the machine and in bearings fixed to the frame of the machine.
I also arrange the driving apparatus (whether actuated by a weight or spring
or by pressure of air or water) so that it is contained within the framework
which supports the machine. In such weighing machines as are arranged to
be actuated by an attendant in one sense for releasing the beam and putting
the machine into weighing, and in the opposite sense to bring back the parts
of the machine to their first position of rest in order the better to ensure
uniformity of action in putting the machine into weighing, I provide a spring
or weight which is wound up by the operator while performing the return
action (which brings the parts of the machine to their first position of rest,)
and on being released expends the power to actuate the machine and effect
the weighing. The action of the spring or weight is controled and regulated
by a conveniently arranged fly.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said James Murdoch Napier in the Great Seal Patent Office on
the 12th July 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
MURDOCH NAPIER, of York Road, Lambeth, in the County of Surrey, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twelfth day of January, in the year of our Lord
One thousand eight hundred and sixty-six, in the twenty-ninth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said James Murdoch Napier, Her special licence that I, the
said James Murdoch Napier, my executors, administrators, and assigns,
or such others as I, the said James Murdoch Napier, my executors,
administrators, and assigns, should at any time agree with, and no others,
from time to time and at all times thereafter during the term therein
expressed, should and lawfully might make, use, exercise, and vend, within
the United Kingdom of Great Britain and Ireland, the Channel Islands,
and Isle of Man, an Invention for "IMPROVEMENTS IN WEIGHING MACHINES,
AND IN APPARATUS FOR REDUCING TO WEIGHT, PART OF WHICH IMPROVEMENTS ARE
APPLICABLE FOR FEEDING BLANKS TO COINING PRESSES, AND TO OTHER MACHINES,"
upon the condition (amongst others) that I, the said James Murdoch Napier,
my executors or administrators, by an instrument in writing under my, or
their, or one of their hands and seals, should particularly describe and
ascertain the nature of the said Invention, and in what manner the same
was to be performed, and cause the same to be filed in the Great Seal
Patent Office within six calendar months next and immediately after the
date of the said Letters Patent.
NOW KNOW YE, that I, the said James Murdoch Napier, do hereby
declare the nature of the said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and by
the following statement thereof, that is to say :-
This Invention has for its object improvements in automaton weighing
machines for weighing and classifying according to weight, and for indicating
the weight of coin and coin blanks (including an improved mode of feeding
such machines with coin and coin blanks, which mode of feeding is also
applicable for feeding blanks to coining presses and other machines), and
improvements in weighing machines for assay purposes, and also in other
weighing machines, as well as in apparatus for reducing too heavy coin

page_text: blanks to weight and in apparatus for reducing assay pieces to a desired
weight.
Automaton weighing machines are in use at the Bank of England, at
the Royal Mint, and in other places, and the present mode of feeding them
is by placing from time to time a number of coins or coin blanks (which I
shall indifferently term "pieces" hereafter) as the case may be, ranged in
single line in an open inclined feeding duct, down which they gravitate as the
lowest "piece" is successively removed by the feeding slide of the machine
to be weighed. To avoid the trouble and attention required to keep the
feeding duct supplied by hand I provide a hollow vessel which I will call the
feeding vessel, into which the "pieces" may be put in the mass without
arrangement; this vessel is by self-acting means gradually emptied of its
contents, so as to keep replenished an inclined feeding duct which directs the
pieces" to the feeding slide of the machine. The flow of the "pieces" from
the feeding vessel is subject to regulation by the weight of the "pieces"
present in the feeding duct. I prefer to place the feeding vessel in connection
with mechanism which will impart to it two movements, by one of which the
bottom of the vessel is raised as in the emptying of a bucket, and by the
other the vessel is made to revolve (to use the same subject for illustration)
in the direction of the hoops on the bucket. By these combined movements
properly timed the feeding vessel may be gradually emptied of its contents,
which as they come from the feeding vessel fall on to an incline formed so as
to direct them into an inclined feeding duct which is closed or partially closed
by a fixed or moveable cover so as to keep the "pieces" in one regular row.
The upper end of the feeding duct is supported by a spring balance weight,
weighted lever, or other means in such manner that when the feeding vessel
supplies the "pieces" too fast for the speed at which they are taken away by the
feeding slide of the machine, and they accumulate in the feeding duct, their
weight will depress its upper end; this action I make available through
suitably arranged connections to check or entirely arrest one or both movements
of the feeding vessel, and consequently the supply of pieces to the feeding duct.
When the number of "pieces" in the feeding duct gets low the reverse action
takes place, and the mechanism which gives motion to the feeding vessel is
put in action for the supply of more "pieces."
This part of my Invention it will be easily understood is also applicable
for feeding blanks to coining presses and to other machines to which such
"pieces" are required to be supplied at regular rates of feeding. When two
or more automaton weighing machines are placed conveniently near together
I concentrate their feeding ducts towards one position to facilitate the supply

page_text: of "pieces" to them when effected by an attendant, and when each machine
is supplied by a self-acting feeding vessel I group these vessels together for
convenience in charging them with "pieces." In concentrating the feeding
ducts of several machines towards one position I so form and arrange them
as to permit an easy flow of the "pieces." When two or more automaton
weighing machines which are placed near together are to be engaged in
weighing a quantity of "pieces" with which they may be supplied without dis-
tinction, I provide an inclined general feeding channel and keep it supplied
with "pieces" either by an attendant or by a self-acting feeding apparatus
from a general feeding vessel. The "pieces" pass down the general feeding
channel by their gravity and are received into the feeding ducts of each
machine. These ducts may be arranged so that when they are sufficiently
furnished the weight of the "pieces" will operate to arrest the supply from
the general feeding channel. Instead of an inclined general feeding channel
down which the "pieces" pass by their own weight a horizontal or con-
veniently inclined general feeding channel may be used, the "pieces" being
moved along it by a propelling brush, or when preferred I employ a carrying
band or bands to keep the ducts of the several machines supplied, which
band or bands may be furnished with "pieces" either by an attendant or by a
self-acting apparatus from a general feeding vessel. I also facilitate the
collection of the "pieces" after they have been weighed and classified by
automaton weighing machines (when two or more engaged in the production
of similar results are placed conveniently near together) by means of inclined
general receiving channels, each of which receives all "pieces" of one class
from the several machines and conducts them to a general receptacle for the
class. Instead of giving an inclination to the general receiving channels in
order that the "pieces" may pass down by their own weight, these channels
may be placed horizontally or at any convenient angle, and a brush propelling
apparatus may be used to move the "pieces" along, or if preferred I employ
a carrying band or bands for collecting each class of "pieces" from the
several machines and delivering them into general class receptacles. I also
employ carrying bands generally in connection with automaton weighing
machines for removing the "pieces" from place to place, such carrying bands
to be arranged with due regard to convenience according to the locality and
to the mode in which the operations of the weighing department are to be
conducted.
In further description of my improvements in automaton weighing machines
I would remark that the present mode of pushing the "piece" on to the
weighing plate by the feeding slide wears away the surface of the plate and

page_text: "
disturbs the adjustment of the machine, and when the "pieces" are bent or
have ragged edges they are liable to catch against the weighing plate. To
avoid these inconveniences I arrange a feeding slide to push the " "piece
into a position where it is supported immediately over the weighing plate, and
near to but not touching it; I then cause it to descend and rest upon the
weighing plate by another movement. After the "piece" has been weighed
it is raised again from the weighing plate before being pushed away.
Instead
of the present long vibrating single channel distributor tube which receives
the "pieces" directly from the weighing plate into its upper and larger end,
and distributes them out of its lower and narrow end according to their class
into one or other of the openings leading to their respective receptacles, I sub-
stitute a fixed mouth-piece to receive the "pieces" after weighing, which
diminishes in size at its lower part until the opening is only sufficient to allow
the "pieces" to pass freely edgewise. Below this mouth-piece I place a
distributor tube divided into as many channels or compartments as the
pieces" are to be distributed into classes; this tube vibrates upon an axis
placed at or near to its lower end, so that the opening to one or other of its
channels or compartments becomes opposed to the opening at the lower end
of the fixed mouth-piece, according to the class the "piece" which has been
last weighed is to occupy. The "piece" passes down the channel in the
distributor tube, and is so directed into the receptacle provided for "pieces"
of its weight. By means of my improved fixed mouth-piece and distributor
tube I am enabled to expedite the action of the machine, as the fixed mouth-
piece can be made much shorter than the present distributor tube, the action
of which is limited owing to the time required for the "pieces" to pass out
of it into the channels connected with the receptacles for the different classes
of "pieces." In order further to expedite the working of the Mint automaton
weighing machine I replace the three-step stop piece now used in connection
with the distributor tube by a stop piece of different form, the middle stop,
or that which serves to direct the medium "pieces," being made to project
more than the stops above and below it, which serve to direct the too light
and too heavy "pieces." This middle stop is provided with a notch along its
thickness, into which the knife end of the retaining stop lever which is in
connection with the testing lever may enter. I adjust my improved stop piece
in position so that when the "piece" is medium weight the distributor tube
as it vibrates towards the end of the stop lever will be arrested when over
the opening for the medium "pieces" by the knife edge falling into the
notch referred to. When the piece is found to be too heavy or too light the
medium stop will miss the end of the stop lever which will be either above

page_text: below it, according to the weight of the "piece," and the distributor tube will
therefore continue its forward vibration until arrested by the too light or too
heavy stop, as the case may be. It is immaterial which of these stops is
placed next in prominence, but should the too heavy stop be so placed the
opening for the too heavy "pieces" will be placed next, and that for the too
light "pieces last. Instead of providing a stop piece to come against the
end of the stop lever to direct the distributor tube over the last channel,
the distributor tube may be allowed to come to rest against a con-
veniently situated fixed stop. I have explained my improved stop piece in
connection with the distributor tube now in use, when it is used along with
my improved distributor tube the channels in the tube must be placed in
suitable rotation. I employ a regulating screw for the purpose of adjusting
the stop piece to its proper position, as it is more convenient than the present
mode and admits of greater accuracy in the adjustment. In order con-
veniently to regulate the range of action of the stop lever in relation to that
of the testing lever (which levers at present are arranged to vibrate together
upon the same centre,) I mount them upon separate centres and connect
them together, so that the testing lever in performing its vibrations will
suitably actuate the stop lever.
In automaton weighing machines arranged for using remedy weights I
attach the double stirrup piece (which raises the remedy weight) to the end
of the pendant and central with it, and the rest for the remedy weight I also
place central with aud below the pendant, so that when the remedy weight is
put into its rest it traverses the vertical line of the pendant. In order to
attain to a very exact and convenient adjustment of the remedy weight to
height I provide a fine screw placed directly under the centre of the rest for
the remedy weight by which it can be raised and lowered at pleasure, and I
prefer to arrange this screw so that it may be accessible by passing the
hand underneath the table of the machine, as in so doing the hand will not
obstruct the view, and for the purpose of causing the remedy weight to be
more clearly seen when in position and more easily got at I deprive the double
stirrup piece of its two outer tie bars, so that the remedy weight can be taken
out and replaced in its rest with much greater facility than at present.
In automaton weighing machines which are to indicate the weight of each
blank, as well as in those automaton weighing machines which are to be used
in combination with my apparatus for reducing the too heavy blanks to a
given weight, I dispense with "remedy weights" and I alter the construction
of the weighing beam, which as at present made has its centre of gravity and
centre of action coincident, or nearly so, that it may respond the more sensibly

page_text: to a very small preponderating weight, and I place the centre of gravity lower
than usual by the addition of an adjustable or fixed weight to the under side of
the beam so regulated in quantity and position that a given amount of
vibration will represent the preponderance of a given weight upon the end
"with a
of the beam. Thus in weighing a sovereign blank or other "piece
beam of this description if a counterpoise is used of the exact standard and the
piece weighed be heavier than standard by one grain, let us suppose that excess
of weight causes the end of the beam upon which it is placed to dip 16th of
an inch, the reverse will take place when the "piece" is one grain lighter than
standard, and by accurately measuring the rise or fall of the beam the weight
of the "piece" ("plus" or "minus" the standard) may be ascertained. To
measure the vibration of the beam produced by the "plus" or "minus" weight
as the case may be of the "piece" weighed, I cause the beam to be retained
in its position by a gripping action as soon as the weighing is completed,
and while it is so retained I ascertain the amount of vibration by a testing
lever, arranged as in the machines now in use; or to ensure greater accuracy I
connect a slide to the end of the lever and apply it against the bottom of the
weighing plate pendant, or to the top or bottom of the counterpoise pendant.
To exhibit the weight of the piece I place an indicator in connection with
the testing lever to be actuated by it. To reduce too heavy blanks to
a given weight I combine my improved apparatus for this purpose, to which
I shall presently refer, with the automaton weighing machine, and I make
the testing lever to influence the reducing apparatus through the medium of
Suitable connections in proportion to the quantity of metal which is to be taken
off each "piece" to reduce them to the proper weight. In automaton weighing
machines which are combined with my reducing apparatus instead of using a
distributor tube to separate the "pieces" into classes they pass down a fixed
tube or guide after being weighed into the reducing apparatus, which receives
each in succession and cutts off the required quantity, and when thus reduced
to the given weight they pass into a general receptacle. When it desired to
reduce the too heavy" pieces" so as to bring them within certain limits of the
standard weight, light or heavy, I arrange the automaton weighing machine to
divide them into four or more classes of weight, as may be found sufficient,
by means of a distributor tube containing the necessary number of channels
and stops to suit, and I provide additional "remedy weights" placed so as to
be acted upon in succession as the beam vibrates; or if preferred my arrange-
ment of a low centre of gravity beam above explained may be used instead of
"remedy weights." When the too heavy blank has thus been weighed and
distributed into its proper channel it is directed into a reducing apparatus
R

page_text: the cutting tool of which is adjusted to take off a fixed quantity, and in
connection with every channel into which the "pieces" are distributed 1
place a similar apparatus, each of which is adjusted to cut off. a different
quantity of metal, according to the class of "piece" it has to reduce. Thus
for illustration, let us suppose the limit allowed on each side of standard to be
of a grain, the too heavy "pieces" will then be more than of a grain
heavier than standard, and if we further suppose the greatest excess of weight
to be grains above standard, the reducing apparatus which is to treat the
heaviest "pieces" should deduct 1 grains, and if the "pieces" are divided
into five classes the second apparatus should deduct 1 grain, the third grain,
the fourth grain, and the fifth grain, and thus the whole of the " pieces
may be brought within the limits of the remedy, although not to the same
weight. In both the reducing apparatuses to which I have referred (namely,
that for adjusting to one weight all the too heavy blanks by taking from each
a quantity varying according to the weight of the blank, and that other which
takes off the same quantity without variation from each blank which it treats,)
I employ a single cutting tool such as suits for turning or plauing, and I place
in front of the cutting edge, or on either side of it, a burnisher stop, which can
be adjusted in its relation to the edge of the tool so as to regulate the depth
of the cut; this burnisher stop and the tool are kept up to their work by an
elastic force, and while the burnisher stop rubs against the surface of the blank
under reduction the tool enters the metal to the required depth, and takes off
an equal cut.
In reducing coin blank blanks I prefer to take the metal from the face of
the "piece" by a circular cut, and in the apparatus which deducts a varying
quantity I employ self-acting means, either to advance and retire the tool
(so as to allow it to take a longer or shorter cut, according to the quantity to
be deducted from the blank under treatment), or to increase or diminish the
distance of the tool from the centre of the "piece," and consequently the size
of the circle cut from its face. In the other reducing apparatus the tool is
adjusted in position so as to take off a certain fixed quantity, and tools of
various widths will be found convenient for the same purpose. Instead of
connecting the reducing apparatuses to work in conjunction with the weighing
machine they may, when preferred, be placed separate, in which case the
reducing apparatus which takes off a varying quantity must be set by hand
for every blank according to its weight, as indicated by the weighing machine,
and to facilitate such setting I provide a suitable indicator. The other reducing
apparatuses, which take off a fixed quantity, will be supplied with classified
blanks from the receptacles of the weighing machine.

page_text: For the purpose of weighing assay pieces and reducing them to weight, as
vell as for weighing the resulting metal to constitute assays, I employ a
weighing machine and reducing apparatus, which I arrange to work more or
ess automatically as may be desired. I prefer to construct my improved
ssay weighing machines with surface weighing plate and pendants instead
of the usual hanging scales. The assay piece or the resulting metal of the
assay, as the case may be, is placed upon the weighing plate, and removed
from it by suitable apparatus working in concert with the other movements
of the machine, or independently actuated by the attendant, as may be
preferred. I use a weighing beam weighted on the under side with an
adjustable or fixed weight such as I have already referred to as applied to my
improved automaton machines for indicating the weight of coin and coin
blanks. When the counterpoise used represents the required weight to
which the assay piece is to be reduced the amount of deflection or dip of the
beam will indicate the excess of weight in the piece, and to measure the
deflection with accuracy and display the result to the attendant, and com-
municate the same when required to the reducing apparatus I employ a fixing
or gripping motion and testing and indicating apparatus nearly analogous to
those which I use in my improved automaton coin and coin blank weighing
machines. Instead of using a counterpoise equal to the required weight of
the assay piece and allowing the deflection only of the beam at the weighing
end to indicate the excess beyond that weight the counterpoise may be
increased to represent in addition to the required weight of the piece the
average excess of weight in a number of pieces. The beam will then vibrate
upwards at its weighing end when the piece is lighter than the average, and
downwards when it is heavier. By this method the weighing may be per-
formed more rapidly, as the vibration of the beam from its position of rest can
be conveniently diminished. To bring the beam to its position of rest, and
to relieve for weighing, a rising and falling horizontal bar similar to that at
present employed in the coin and coin blank automaton weighing machines
may be used to act upon the pendants, but I prefer to employ for the purpose
a vertical gripping action applied against a horizontal bar attached to or
forming part of either one of the pendants or otherwise connected to the
weighing beam, the grippers being arranged to open and close in the direction
in which the bar against which they act vibrates, and they are capable of
adjustment to height, so that when they come together upon the bar the beam
will be in its proper position of rest, and they are opened and closed at the
Instead of
desired speed and at the proper times by a suitable cam motion.
acting to grip a bar they may, if preferred, be arranged to act in the reverse
B 2

page_text: sense against the top and bottom of a suitably formed opening. This mode o
setting the beam to position and releasing it for weighing is also applicabl
to coin and coin blank automaton weighing machines and to other weighing
machines.
In automaton coin and coin blank weighing machines, as well as in assay
weighing machines, when it is desired to obtain a quick and clear release of
the beam for weighing, I apply grippers for releasing the beam for weighing
which are arranged to open and close horizontally or at right angles to the
direction in which the portion against which they act vibrates when the beam
is released for weighing. When grippers so arranged are employed for
releasing the beam for weighing, the setting of the beam back to its position of
rest may be accomplished by either of the methods just described or by other
suitable means.
In weighing the resulting metal of the assay by means of my improved
assay weighing machine just described it will be desirable, as recommended
in the case of assay pieces to use a counterpoise of such a weight as will
be about equal to the average load, so that the beam may vibrate upwards
as well as downwards at the weighing end and indicate the "plus" or
"minus," weight as the case may be. In this process of weighing the arrange-
ments which I make for connecting my assay weighing machines when used
for weighing assay pieces with the reducing apparatus are not required. I
employ the usual means for preparing the assay pieces by reducing the metal
to a convenient thickness, and afterwards cutting out with a punch a disc of
suitable dimensions, but in order that I may be able to effect the exact
reduction of these discs to a given weight by my reducing apparatus, notwith-
standing their varying specific gravities, I employ more than the usual care to
ensure that in assays of gold all the discs or assay pieces shall be precisely of
one thickness and of one diameter, and that for silver assays the discs (which
are usually made larger than in the assays of gold) shall also be as nearly as
possible of one diameter and one thickness. It will be understood that when
assay pieces of equal or nearly equal volume are weighed in my assay weighing
machine the indicated excess in each piece beyond that weight to which it is to be
reduced will be in proportion, or nearly so, to the specific gravity of the piece. I
therefore arrange my reducing apparatus for assay pieces to deduct proportionally
less metal per grain or part of a grain of excess when the excess in the weight of
the piece is large, and proportionally more when the excess in weight is small,
so as to bring the pieces all to the same weight. This I accomplish when
the reducing apparatus is to work with the weighing machine (to be influenced
by it to deduct the proper quantities) by placing in connection with the

page_text: testing lever a suitably formed incline to regulate and proportion the action
which is communicated to the reducing apparatus, so that it will be increased
per unit of weight when the quantity to be deducted is large, and decreased in
the same relation when the quantity to be deducted is small. I also use a
spirally formed plane for this purpose arranged to act directly on the beam or
on one of the pendants, or indirectly through the medium of a testing lever...
When the reducing apparatus is used separate from the weighing machine the
weight of the piece must be noted by the attendant, who will also set the
reducing apparatus to take off the proper quantity by means of an indicator
provided for the purpose. The assay pieces may be reduced to weight in the
manner I have explained for reducing coin blanks to one weight, and with
the same description of cutting tool and burnisher stop, but as the quantity to
be deducted in the case of assay pieces is often much larger in proportion to
the size of the piece, and as it is also of little consequence from what part of
the piece it is taken, I prefer to employ a punch cutter to cut into the piece
from the edge. The piece takes its position by coming against a stop slide
which is adjusted in relation to the cutter punch according to the weight of
the piece (either by its connection with the weighing machine or when separate
from it by the attendant, who sets the reducing apparatus by the indicator,) so
that the piece comes more or less under the cutter punch, and a notch is cut
in it beginning at its circumference and arriving more or less near to its
centre according to the weight of the "piece." When it is found difficult to
attain to a result sufficiently accurate in one process of reduction I arrange
the first reducing apparatus so as to leave a small excess of weight in each
piece, and I re-weigh them to ascertain the exact amount of such excess, and
again treat them in a reducing apparatus suitably adjusted to deduct the
excess, and provided with a fine tool for the purpose. In making this last
reduction the specific gravity of each piece, as indicated by its first weight, or
the quantity of excess of weight first deducted from it, may be taken into
account and allowed for in the adjustment of the second and final reducing
apparatus, and for this purpose I provide additional means of adjustinent to
correct and proportion, in accordance with the specific gravity of the piece, the
quantity in volume to be deducted from it in order to secure the exact
reduction of the ascertained excess of weight.
My improved arrangement of a weighing beam weighted on the under side
with an adjustable or fixed weight (so that the amount of its vibration will
represent the difference in weight between the counterpoise and the load
weighed) combined with a fixing or gripping apparatus for retaining the beam
in its position after weighing and a measuring or testing apparatus for

page_text: ascertaining the exact quantity of vibration while the beam is so retained by
the grippers, with an indicator attached for exhibiting that quantity to the
weigher, is applicable to other weighing machines, and more especially for
checking quantities which have been already weighed, and for which the
proper counterpoise can be readily selected. In other cases a counterpoise
sufficiently approximating to the weight of the load may be found by trial.
This mode of weighing enables me to dispense with the use of small weights,
and to obtain very accurate results with great facility. When I employ a
vertical gripper-releasing action, such as I have explained in connection with
my improved automaton and assay weighing machines, for finally releasing the
weighing beams of such machines as are used for weighing bullion and other
heavy weights, I arrange it to act in concert with any other ordinary con-
venient mode of releasing the beam, and I construct the gripper-releasing action
to effect the release of the beam only when the load is within a given limit of
the weight of the counterpoise. In bullion weighing machines which are
furnished with grippers opening horizontally to release the beam finally when
the load and the counterpoise are nearly equal I place the grippers upon an
axis so that they will vibrate with the beam when the difference between the
load and the counterpoise exceeds a given limit. For convenience in applying
power to automaton weighing machines I place a driving shaft below the level
of the machine and in bearings fixed to the frame of the machine. I also
arrange the driving apparatus (whether actuated by a weight or spring or by
pressure of air or water) so that it is contained within the framework which
supports the machine.
In such weighing machines as are arranged to be actuated by an
attendant in one sense for releasing the beam and putting the machine into
weighing, and in the opposite sense to bring back the parts of the machine
to their first position of rest in order the better to ensure uniformity of action
in putting the machine into weighing, I provide a spring or weight which is
wound up by the operator while performing the return action (which brings
the parts of the machine to their first position of rest,) and on being released
expends the power to actuate the machine and effect the weighing. The
action of the spring or weight is controlled and regulated by a conveniently
arranged flv.
Drawing No. 1 represents my improved feeding apparatus; A is the feeding
vessel which is placed in a receiver B, in which it is held by the spring catch
a. The receiver B is placed within the tipping frame C, and is furnished at

page_text: its lower end with a short spindle which passes through the lower bar of the
tipping frame. Upon the projecting end of this spindle the worm wheel o is
fixed; the tangent screw d works into it, the power being applied through
the fast pulley 6, the speed pulleys f and 9, and the spindle h, which has its
bearings in arms projecting from the tipping frame, thus as the tangent screw
turns the receiver B turns also, although at a much slower rate, and carries.
round with it the feeding vessel A. The pinion is also fixed to the spindle
on the lower end of the receiver B, this pinion gears with wheelj upon spindle
, motion is thus communicated to the worm m, which acting in the fixed
worm wheel n raises the tipping frame upon its centres at o; and with it the
receiver B and feeding vessel A. The worm wheel is kept fixed in its
position by the ratchet pall p which works upon a pin fixed in the upright of
the frame D at 9; the pall takes effect in the teeth of the internal ratchet r
forming part of the worm wheel n. When the feeding vessel is tipped to the
position A¹, shown in Figure 1 by red lines, it may be lowered by raising the
pall p, and gently letting the tipping frame down by hand. The tipping
frame may also be raised by hand to any desired angle, and the ratchet m will
keep it in position. The pivot of the tipping frame to the right hand in
Figure 2 is extended beyond its support, and the lever of the balance weight
is fixed to it. This weight is provided to counterpoise the weight of the
tipping frame, and the parts attached to it, as well as the weight of the feeding
vessel and its receiver. When the apparatus is in operation the " pieces"
as they come from the feeding vessel fall on to the incline E, which is formed
so as to direct them into the inclined feeding duct F, which has a moveable
cover G provided with hinges that it may be conveniently opened and closed.
The upper end of the feeding duct is supported by the spring s acting through
the lever t, which is in connection with the bell-crank lever u, the forked end
of which embraces the driving cord which in the Drawing is shown upon the
fast pulley e. The feeding duct is also shown in its raised position, or that
which it occupies when ready to receive more "pieces," but should they
accumulate in it their weight will depress its upper end and cause the lever t,
upon the one end of which it rests, to actuate the bell-crank lever so as to
pass the driving cord from the fast pulley to the loose pulley k, thus the
tipping and turning motions of the feeding vessel will be arrested. until the
number of pieces in the feeding duct has diminished, when it will be raised
by the springs, and at the same time the bell-crank lever will pass the
driving cord on to the fast pulley e, and so set the tipping and turning motions
of the feeding vessel into action for the supply of more " pieces."
Figure 1, Drawing No. 2, indicates in plan six automaton weighing

page_text: machines A with their feeding ducts a concentrated towards one position a
B so that they may be supplied conveniently from one reservoir; these feeding
ducts may be open and inclined in the usual way. It will be easily under
stood that when each machine is supplied by a self-acting feeding vessel they
may be grouped in a similar manner. Figures 2, 3, and 4 shew my
arrangement of a general feeding channel and general collecting channels
I have indicated in the Drawing three machines which are supplied with
"pieces" through the general feeding channel A, and the several classes of
pieces are collected from each machine by the general collecting channels
B, C, D, into the receptacles B, C, D. The general feeding channel A may
be kept supplied with "pieces" either by a self-acting feeding apparatus such
as I have described, or by an attendant who may have the "pieces" con-
veniently at hand in the reservoir E. The pieces pass down the general
feeding channel A by their gravity as it is inclined, and are received into the
feeding ducts F of each machine, and the surplus "pieces" which may pass
along the general feeding channel without entering either of the feeding
ducts will fall into the receiver G, from whence they may be transferred to
the reservoir E at pleasure. Figures 5, 6, 7 illustrate in natural size a portion
of the general feeding channel A, and one of the inclined feeding ducts F,
and the manner in which the one is supplied with "pieces" from the other.
The pieces roll on their edge in a gutter a, and as they roll they are caused
to lean over to the one side and rest against the bar b; the outer edge of
the gutter is only required to be raised enough to keep the "piece "in position;
ns the "piece" passes down the general feeding ohannel A, it would without
interruption go on until it falls into the receiver g, and this would take place
if all the feeding ducts of the three machines shewn were sufficiently supplied,
but when either of these feeding ducts requires more "pieces" the spring c
raises the upper end of the feeding duct F until the spring d catches in the
notch as shown in Figure 5, by which time the slide has been pushed
forward by the pin f (which is in connection with the feeding duct) acting in
the inclined fork of the slide e; when the slide e is thus forward, as will be
seen clearly in Figure 6, the onward progress of the "piece" is arrested, and
it is made to pass through the opening H in the bar b, and into the feeding
duct F; when the "pieces" accumulate in the feeding duct F their weight
overcomes spring d and, spring c, and the upper part of the feeding duct F
descends until spring d catches in the notch g. In its rising and falling
actions the feeding duct F works upon its centre at h. Figures 8, 9, and 10
illustrate the application of a carrying band employed as a general feeder; I is
the carrying band, which should be caused to move at a convenient speed by

page_text: may
be
passing over revolving pulleys or drums. The band is made rather more
than half the diameter of the piece in breadth, so that when pushed a little
way off the band by the slide the "piece" will fall into the feeding duct F.
The slide operates in the same manner as already described in reference to
Figures 5, 6, and 7; should any surplus pieces pass on when the feeding ducts
of the several machines are supplied, they may be returned to the reservoir
by a carrying band arranged for the purpose. My propelling brush
made in a continuous form as a band brush, and may be kept in constant
motion by placing it on revolving pulleys or drums as in the case of my
carrying bands. The propelling brush works in a channel, and lying upon
the "pieces" carries them along with it until they are received into the
feeding ducts of the machines. I have not thought it necessary to furnish
a drawing of the propelling brush, as the above description will make it
clearly understood. In this application also the slide will serve to direct
the "pieces" into the feeding ducts as already explained.
In Drawing No. 3 a is the weighing plate or rest for the "piece" which
is to be weighed. The feeding slide b, actuated by lever A and cam B in the
usual way, pushes the "piece" on to the plate c, and exactly over the weighing
plate a, the surface of which is slightly lower than that of the plate c, so
that the "piece" as it is pushed on will not touch the weighing plate; the
plate c is then allowed to descend by the action of cam C, against which the
roller at the end of lever D operates. This lever is made fast upon the same
spindle with the levers d, d, which support the plate c by its depending slides
e, e, the springs f, f, being so set as to press the plate c down when the
smaller diameter of the cam C is presented to the roller on the end of the
lever D (which is the position when the piece is allowed to rest upon
the weighing plate), and when the larger diameter of the cam C acts against
the roller on lever D the plate c is raised through the medium of the levers
D and d, d, against the force of the springs f, f. When the plate c is raised
the next piece is pushed on by the feeding slide, and the last weighed
piece" is displaced by it. E is a fixed mouth-piece into which the
pieces pass when they are displaced from the plate c; below the mouth-
piece E is placed the distributor tube F, which is shown in the Drawing
with three compartments, and vibrates upon an axis at g. The vibrations of
distributor tube F are timed by the cam h against which the roller on the
end of the lever G acts by the force of the spring H; i is a stop piece, the
middle stop or that which directs the medium "pieces" being made to project
more than the stops above and below it; j is a screw for regulating the stop piece.
to height; I is the stop lever against which the stop piece i acts. To direct
"

page_text: the distributor tube F so that the outermost or last channel comes opposite the
fixed mouth-piece the projection k on the distributor tube may be used to
come against the fixed mouth-piece E, which will form a stop for it. It
will be observed that the testing lever J and the stop lever I are mounted
upon separate centres. The testing lever is actuated by cam / through lever
K and connecting rod m, and while the testing lever performs its vibrations
the stop lever is suitably actuated, the connecting rod m being formed at m¹
so as to depress the stop lever when the testing lever falls, and to allow the
stop lever to remain down during the rise of the testing lever, the stop lever
being balanced as at present, so that its stop end tends upwards. To bring
the beam to its position of rest after weighing, and to relieve it for weighing
instead of the rising and falling horizontal bar at present employed,
which acts upon both pendants, I have shewn my improved vertical relieving
grippers L, which are actuated by the cam n through lever n', connecting
rod n³, lever n³, and the double cam n', and are applied against the horizontal
bar o which forms part of the weighing pendant, the vertical relieving
grippers L are brought together by the spring n³, the upper limb of the
grippers coming to. rest against the rest ne, which projects between them, and
which may be regulated in height as desired, so that when they come together
upon the bar o the beam will be in its proper position of rest. The gripping
motion M is similar to that usually employed, and its mode of action is the
same, the camp which controuls it causes it to open immediately after the
piece" is placed upon the weighing plate in order that the beam may be
free to weigh; after sufficient time has been allowed for weighing, during
which time the relieving grippers have been opened gradually by the action of
the cam n, the grippers M close and hold the weighing pendant in the position
which it may then occupy according to the weight of the piece. The
testing lever is then allowed to fall in the usual way by the action of its cam
until its end rests upon the bar in the pendant end at o', the connecting rod
of the testing lever acting in its descent upon the stop lever at m¹ brings it
down with it, and the distributor tube coming forward in its turn by the
action of its cam its stop comes against the stop lever at such a height as is
"
When I desire to obtain a
in accordance with the weight of the "piece."
quick and clear release of the beam for weighing I so modify the cams above
referred to and the times of their acting as to cause the vertical relieving
grippers, as I have termed them, to open quickly, while the holding grippers
M remain closed, and then I cause these last to open to relieve the beam
for weighing, and after a short interval, which is allowed for the weighing to
take place, they are closed again, when the testing lever acts in the usua

page_text: way; the grippers M are again opened, and while they so remain the vertical
relieving grippers close and bring the beam in to its position of rest.
Figures 1, 2, and 3, Drawing No. 4, illustrate my improvements above
referred to in the mode of arranging and adjusting the remedy weights. The
double stirrup piece a, which is attached to the end of the pendant 6, is
deprived of its two outer tie bars, which leaves it open for the more convenient
reception of the remedy weight c. The rest d for the remedy weight is
placed central with and below the pendant 6, and it is adjusted to height by
the fine screw e and nut f. The spring 9 passes round the quill h, which is
part of the plate h³, which is secured by screws to the table A of the machine;
this spring acts below upon the fixed collar i, and above against the sliding
collar j, which has a small pin passed through it and through the stem of rest d
(at the end of which stem is the fine screw e), and also through long free holes
in the quill h, in which long holes the pin works when the rest d is raised or
lowered. The spring 9, therefore, by its pressure against the collar j raises the
rest d when the rest f is unscrewed, and when the nut is screwed up the spring
is compressed at the same time that the rest d is lowered. It will be observed
that the nut can be manipulated from the under side of the table A.
Figures 4, 5, and 6 indicate the mode in which I arrange additional
remedy weights, which are to be acted upon in succession as the beam
vibrates in machines which are intended to separate too heavy" pieces" into
several classes of weight. If the "piece" is in excess of the upper remedy
weight a it is raised by the upper stirrup rest; if it preponderates still more
the second remedy weight a¹ is raised, and if still more the third remedy
weight a is raised.
Drawing No. 5. Figures 1 and 2 represent a weighing machine con-
structed with a weighing beam, the centre of gravity of which is much lower
than usual by the addition of the weight a, and regulated so that a given
amount of vibration will represent the preponderence of a given weight upon
the end of the beam; I have arranged this machine to be actuated by an
attendant by means of the handle A. The attendant moves the handle to the
right and makes one turn, when the spring b retains the handle in the position
shewn in the Drawing. When the "piece" to be weighed is placed upon the
weighing plate b, by hand or by mechanical means as may be desired, the
operator pushes the end of spring c and relieves the handle A, which is held
by a projecting catch of the spring. When the handle is relieved a clock
spring which is contained in the spring box B (and which is wound up by the
operator after each time of weighing) has to turn the spindle C in the direction
of the arrow, and until the handle A passes once round, when it comes in

page_text: contact and stops against the catch of the spring c, the various movements of
the machine having by that time been completed, and the weighing having
been effected. The action of the spring in spring box B is controlled by the
fly D which is placed upon the spindle d, which has a small pinion upon it
gearing with the wheel upon spindle C. Spindles E and F revolve in virtue
of their connection with spindle C. In the Drawing the machine is shown
wound up and ready for weighing, and upon the handle A being released by
pressing the spring c the grippers G actuated by cam e will open, after which
the cam will (through the levers and connecting rods e, e,,) open gradually
the vertical relieving grippers H in the manner I have already explained,
with reference to Drawing No. 3. When the grippers have become fully
opened the grippers G close, and the testing lever I is allowed to descend by its
cam g, and lever and connecting rod 9' and g³ until the testing lever I comes
in contact with the bar h in the pendant J. At the extreme end of the testing
lever is attached a chain which passes over and is fast to a small barrel on the
indicator spindle i, and upon the same spindle is placed pulley j, to which is
attached another chain, at the end of which is suspended a weight. Thus
when the testing lever I descends it turns round the indicator spindle i and
the pointer k which is fixed to it until the lever I comes in contact with the
bar h in the pendant, which arrests its motion. The pointer will then indicate
on the dial the difference between the load weighed and the counterpoise, the
divisions on the dial to the right hand will indicate the minus weight of the
load weighed, supposing it is placed upon the weighing plate J', while the
divisions to the right hand will represent the plus weight of the load. The
machine has thus effected the weighing and indicated the plus or minus weight
of the load, and the handle A has made its revolution by the action of the
spring in box B. The operator must now turn the handle A once round in
the opposite sense to that in which it is worked by the spring, and the machine
will be found to be true for another weighing. Figure 3 shows an arrange-
ment by which instead of the testing lever acting against a bar in the pendant
to ascertain its height the result is arrived at by connecting to the end of the
testing lever the chain l, to which is attached the inclined slide 1, as the testing
lever I descends the slide is drawn towards the end of the pendant J by the
balance weight until it comes against it, when the progress of the inclined
plane Z is arrested. The indicator by its connection with the testing lever
will exhibit the result as before explained; is an abutment which prevents
the pendant being pushed away by the action of the inclined slide . Figure 4
indicates a spirally formed plane m which serves the same purpose as the
inclined slide shewn in Figure 3.

page_text: Drawings 6 and 7 represent the combination of my improved apparatus for
reducing too heavy blanks to a given weight with the automaton weighing
machine..
In each Figure in the Drawings I have shewn only a certain portion
of the whole machine in order to enable me to define the parts clearly, it is
therefore necessary to refer to both Drawings in order to understand the
description. The testing lever A (which is arranged in a manner nearly
similar to that which I have just described in Drawing No. 5, Figure 4,)
influences the reducing apparatus through the medium of the fine chain a
which is passed round and attached to the pulley a'. The extent of the
action of the testing lever (as I have already explained) is controuled by the
position which the load weighed causes the beam to occupy, and consequently
by the height of the pendant, which is ascertained by the spirally formed
plane 6 when caused to turn on its axis by the action of the testing lever A
until it is arrested by coming against the end of the pendant, which at the
time is held firmly by the grippers B, which are actuated in the usual way by
cam 6. It will therefore be understood that the action of the testing lever
varies in quantity according to the excess of weight in the piece weighed,
(the beam C being constructed with the centre of gravity below the centre of
action as I have already described). Thus the pulley a¹ will, through its
connection with the lever A, be turned round a greater or lesser part of a
revolution, according to the excess of weight in the piece weighed. The face
cam a will also partake of this motion as it is made fast upon the spindle a³,
upon which also the pulley a¹ is fixed; pulley a with its chain and weight a
and a serve to keep the chain a under tension and to return the face cam a
to its first position when the lever A is raised. The pulley b¹ and its chain
and weight 62 and 3 serve to keep the chain c under tension; this chain cat
one end is connected to lever A, and the other passes round and is fixed to
the small pulley which is in connection with the spirally formed plane b.
The weight bit will be seen turns the spirally formed plane as the lever A
descends, and when the lever A is raised the spirally formed plane 6 is turned
back to its first position, or that in which it is shewn in Figure 1; the weight
63 being wound up at the same time to the position in which it also appears in
Figure 1. The face cam a is placed within the hollow fixed face cam d, at
the centre of which the spindle a³ has its bearing; the fixed face cam is
supported by the standard D. The ring faces of these cams are shewn at
Figure 11, about one-third of the circumference of each of them is lower than
the other two-thirds. The face cam a³, as I have before shewn, turns round
a quantity corresponding to excess of weight in the piece, so that as the cams

page_text: are placed in relation to each other in Figure 11 they indicate the greatest
limit of excess in the weight of the piece, and if a roller were to run upon the
face of them it would run one-third round upon the low surface, and the
other two-thirds upon the raised surface, but if the face cam a³ is not turned
round so far (as will be the case when the piece is less in excess,) and only
arrives at the position marked y', the roller will then run upon the low
surface for only about one-sixth part of the revolution, as it will meet with
the raised surface at y¹, and again, if the piece is but very little in excess of
the weight to which it is to be reduced, the open portion between the two
cams will be less.
Having explained the action of cam a' in relation to the fixed cam d, I will
proceed to show the manner in which they influence the reducing tool.
Roller is attached to the end of lever f³, and at the opposite end the lever is
jointed in the hollow rotating carrying head E at g, the rod g¹ is jointed to the
lever and is carried round with it. The rod 9' forms a pivot for the rod g¹
and does not turn round, it is pressed against the rod g' by the spring F
which is connected to lever G, which has its fulcrum at h, and at h' is attached
to the cutter shaft H, which is arranged so that it can be moved on end in its
bearings while it revolves. By means of the connections which I have just
described the action of the face cams a³ and d upon the rollerfis communicated
to the cutter shaft H, so that when the roller f is running upon the raised surface
of the cams the lever f¹, rods 9' and 9³, and lever G are forced back, and the
cutter shaft is also drawn back. The wheelwork is arranged so that the cutter
shaft makes three revolutions for one of the hollow carrying head E, and allow-
ing one-third of a revolution to be the greatest distance the roller f can run on
the lower surface of the face cams, the cutter shaft would in that case remain
in its forward or acting position during one revolution of the cutter i; it
would then be withdrawn, and during the time the roller runs on the raised
portion of the face cams or during two revolutions of the cutter i the cutter
shaft would be drawn back out of work. When the roller f runs upon less
than one-third the circumference of the face cams the cutter shaft will be
withdrawn before it has made a revolution, and in accordance with the weight
of the piece so it will be seen that the cutter r is allowed to remain a longer
or shorter period in its forward acting position, so that the cut which it takes
from the piece presented to it is more or less in proportion to its excess of
weight. The piece is placed to be weighed on the weighing plate, and after
it has been weighed and the excess of weight noted by the position taken up
by the face cam a' it is displaced and passes down the fixed tube or guide I
into the holder box J. The front of this box towards the cutter i is open.

page_text: On entering the box holder J the piece comes to rest against the small pro-
jection j, Figure 4, at the bottom side of the holder K. The holder K comes
forward as cam k presents its smallest radius to the roller ¹ which runs
on a pin fixed in the projecting guide end of holder K, the spring L forcing
the holder forward by acting against the collar which is fixed to the neck of
the holder K, thus the piece is held between the holder and a narrow ring of
metal forming the front of the holding box, the hole in the front of the
holding box being made purposely too small to allow the piece to pass out.
The piece being firmly fixed in the holding box it is in a státe to be operated
upon by the cutter i, which I have already explained. When the cutter has
taken off the required quantity the cam k acts upon the roller k¹ and forces
back the holder K against the pressure of the spring L and releases the piece,
which passes down the channel M into a general receptacle. The cam k
then allows the holder to return to the position shown in Figure 1 to be ready
for the reception of the next piece. In order to fix the face cam a³ while
the roller funs over it I provide the break m, which is at the end of lever N
and passes through an aperture in the fixed face cam a³, so as to come against
the periphery of the face cam a². The lever N is pressed down by the spring n,
and is caused to rise and fall at the proper times by the raised portion o
provided on the circumference of the carrying head E, which acts against the
roller P, which is on the end of the break lever N.
Figures 7, 8, 9, 10, 11, 12 shew the cams used for the various move-
ments of the machine. I have not thought it necessary to describe the
action of my vertical relieving grippers for relieving the beam for weighing and
for bringing it back to rest, as I have already done so fully in connection with
Drawing No. 8.
Drawing No. 8 represents my reducing machine, which is arranged to
take off a fixed quantity from each piece. A is the feeding duct; a, the
feeding slide actuated by cam a¹ through lever a³ and connecting rod a³. The
piece" is pushed forward by the feeding slide a until it arrives immediately
under the cutter head B; when the "piece" is so placed the cam C allows lever
C', which passes through an aperture in the upright D to descend, so that the
spring E acting against the fixed bracket F may through the cross head
G, uprights c, c, and upper cross head F, bring down the cutter spindle B*
and cutter head B until the cutter has made a revolution and cut away in a
circular form the required quantity from the "piece" under reduction. As the
cutter end descends with the uprights c, c, the holding springs d, d, are brought
down also, and in their descent they first press against the "piece" before the
cutter comes fully down, so that the "picce" is held before the cutting tool com-

page_text: mences to act. After the cutter has operated upon the "piece" the cutter head
B rises by the action of cam C (on the roller at the end of lever C¹), the
holding springs also rise by the same action, and the "piece" is free to be pushed
off by the next on-coming "piece" and falls into the channel G, whence it
passes into a convenient receptacle. H is the driving pulley from which the
power is communicated to its shaft H', upon which are fixed spur wheel I,
which gives motion to wheel I', which gears into it, and which is fixed on
shaft J, upon which the cams a' and C are placed. The mitre wheel K is
also fixed on shaft H' and gears with mitre wheel K³, which is placed upon
the lower end of the upright shaft K. The upper end of this shaft carries
a spur wheel L, which gears into the wheel L, which is fixed on the upper
end of the cutter shaft B. Thus motion is communicated to the cam
shaft J and to the cutter shaft B³. The retiring spring M withdraws the
feeding slide, when the cam a¹ permits. The cross bar N acts against the
boss of wheel L when the cutter is raised. Figure 4 shows in section to a
larger scale, the cross head G revealing the pressure point which is backed
by a spring contained in the cross head. Figure 5 shows the cross head G
in plan,
Figure 6 represents the cutter head to a larger scale with the
cutter in contact with the "piece." Figure 7 shows the cutter head in
section, and the manner in which the cutter is fixed. The cutter f is here
represented acting on the "piece" which is held down by the holding springs
d, d. Figure 8 shows the cutter head partly in section and the burnisher
stop e acting against the "
piece." Figure 9 shows the cutter bar B' in
section, and below it in plan the cutter head B with cutter f and burnisher
stop e, also the holding spring d, d, acting on the "piece." Figure 10 shows
the "piece" with the circular cut indicated such as is made by the cutter f.
Drawing No. 9 illustrates that form of my improved reducing apparatus
which is set by hand to reduce the quantity required according to the excess of
weight in the "piece." The "piece" (the weight of which must have been ascer
tained) is placed in the guide A, when it falls against and is retained by the
projecting piece a, which is on the under side of the holder B. The lever C
(which is shewn in the Drawing full forward) being at such time back about
the one-half of its throw, in which position the catch 6 on spring c will retain
it. When the "piece" has come to rest against the projection a the button d
may be pressed down, which will cause the lower end of the lever C to be
disengaged from the spring catch 6, and the spiral spring D which takes its
.abutment against the head of the fixed frame E will force the holder B
forward against the "piece," and fix it against the front plate of the holding
box as shown in the Drawing. When the " piece" is so held the clamp

page_text: screw e of the setting lever I may be loosed, and the indicator lever which
works freely upon the fixed pin may be turned. round at pleasure, and be
set by its pointer 9 to a suitable division: upon the. dial G, in accordance with
the weight of the "piece." The indicator lever may then be fixed by the clamp:
screw 6, and the cutter may be moved forward by the lever H. The lever H
is retained in its forward position by the spring catch 9 which passes through
a hole in the support. If the working crank handle I be now turned in the
direction of the arrow it will turn the mitre wheel J which is fast with it
(they both turn free upon the fixed pin f) and motion will be communicated.
to the mitre wheel K which is fast upon the cutter. bar L, thus the cutter
will be turned round less or more in accordance with the motion given to the
handle I; in the position which the handle I occupies in the Drawing it is
brought up against a fixed stop h which is its position of rest from which its
departure is always taken, and the amount of its motion depends upon the
position of the indicator lever. The indicator lever carries with it when it is
tmoved the stop i, against which the handle I comes, but before the handle is
moved the clamp screw e should be tightened so that the handle may not
displace the stop i when it comes against it. The dial is made fast to the
fixed pin f. It will therefore be understood that according to the excess of
weight in the piece the indicator lever F is moved round (in the direction of
the arrow) away from the handle 1, when the "piece" is much in excess the
indicator is moved further round, and when the excess. is small it is only
moved a short distance away from the handle I, the face of the dial plate is
divided to facilitate the accurate setting of the indicator lever F to the
quantity required, according to the quantity to be cut from the "piece."
Figure 4 shews the cutter head, being a section taken through W, X, in
Figure 2.
I have shewn the cutter and burnisher stop placed in an adjustable
slide with screws k, k, by which the tool may be set further from or nearer
to the axis of the cutter head so that the circle it describes may be made
larger or smaller to regulate with nicety the quantity of metal which the
cutter removes. When the piece has been reduced the end of spring / should
be pressed to relieve the lever H, which will be drawn back by the spring m
and the lever C should be thrown full back to withdraw to its full extent, the
holder V, which will allow the piece to pass the projecting piece ȧ, and
fall down the channel O into the conducting tube P.
Drawing No. 10 illustrates my reducing apparatus. arranged for reducing
assay pieces to one weight. The assay piece a is passed under the two
holding-down plates b, b, and takes its position. by coming against the end of
the stop slide c, which is adjusted in relation to the cutter punch.e.according
C

page_text: to the weight. of the piece which comes more or less under the cutter punch
e, which when the hand lever A is forced down cuts a notch in the "piece,"
beginning at its circumference, and arriving more or less near to its centre
according to the weight of the "piece.". The setting of the slide to its proper
position is done. by means of the divided circle B and the fixed pointer C,
the circle B is made fast to spindle f, which receives the screwed end of the
slide c, so that as the spindle fis turned round the slide c will be moved along:
in its bed in the top plate D of the machine; g is a plate which covers the
slide c; worm wheel E is placed on spindle f, and is acted upon by the
worm k. By turning the milled, head i, which is fast on the end of the
worm spindle, the divided circle will turn slowly, and the divisions upon it
can be accurately set to the pointer C. The divisions upon the circle B
(which will indicate units of weight) should decrease in distance from each
other as the circle B turns round from the first position, which position must
indicate that the slide c is placed so that the cutter punch in its descent
would only touch the edge of the piece when placed against the slide. The
gradual decrease in the pitch of the divisions is necessary to make allowance
for varied specific gravities of the pieces.
Drawing No. 11 is my reducing apparatus for carrying out a second process
of reduction in order to attain to great accuracy in the [reduction of assay
pieces. The system is the same as that which I have described in connection
with Drawing No. 10, but I introduce the lever A, the fulcrum of which a
is variable by means of a slide b and screw c. On the projecting end of the
screw c there is a milled head by which it can be turned, and the dial d and
pointer e serve to set the fulcrum a of the lever A in its proper position
according to the original weight of the " 'piece," which should be recorded in
order that when the second reduction is to be made the specific gravity of the
piece may be taken into consideration and allowed for by the position of the
fulcrum of the lever A, so that if the piece has originally been very heavy
and a large cut has been taken out of it by the first process of reduction,
in the second reduction of the small remaining excess the fulcrum of the
lever A should be set to approach the centre g, so as to reduce the proportion
of advance of the top slide when it is set by the indicating dial and pointer
B and B'. It will be seen that the worm j acts in the lever A, and that
the lever is attached to slide h at g.
Drawing No. 12, Figures Nos. 1 and 2 shew my mode of more con-
veniently applying power to automaton weighing machines. A is the driving
shaft, which I place below the level of the machine B and in bearings C
which are fixed to the frame of the machine. The shaft A may pass along

page_text: to any number of machines, and may have a pulley placed upon it at any
convenient position to connect it with the prime mover; D is a pulley for
tightening the driving cord, which passes upwards and round the pulley which
is upon the first motion spindle a of the machine.
Figures 3 and 4 shew an arrangement of spring driving apparatus which
is contained within the framework of the machine. E is the spring case
fixed to the wheel F which drives pinion and wheel G which are on the
same spindle; pinion c gears with wheel G, and on the same spindle with
pinion c is the pulley for driving the machine, round which a cord may be
placed for that purpose; pinion d upon the fly spindle gears with wheel H,
and the fly I regulates the motion to wind up the main spring in case E.
I have provided a lever with ratchet pawl acting in ratchet wheel J, and a
pawle working on a pin which is fast in the frame of the machine prevents
the spindle f from turning back by catching in the ratchet wheel K. The
main spring is attached to spindle f at its one end and to the spring case at
the other, so that the turning of the spindle f winds up the spring as in
ordinary clockwork.
In witness whereof, I, the said James Murdoch Napier, have hereunto
set my hand and seal, this Twelfth day of July, in the year of our
Lord One thousand eight hundred and sixty-six.
JAMES M. NAPIER. (L.S.)