IMPROVEMENTS IN WEIGHING MACHINES
Year: 1840

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, MARK
FREEMAN, of Sutton Common, in the County of Surrey, Gentleman, send
greeting.
WHEREAS Her present most' Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Tenth day of September, in the fourth year of Her reign,
'did, for Herself, Hér heirs and successors, give and grant unto me, the said
Mark Freeman, Her especial licence, full power, sole privilege and autho-
rity, that I, the said Mark Freeman, my exors, adññiors, and assigns, or such
others as I, the said Mark Freeman, my exors, adññiors, or assigns, should at:
any time agree with, and no others, from time to time and at all times during
the term of years therein expressed, should and lawfully might make, use,
exercise, and vend, within England, Wales, and the Town of Berwick-upon-
Tweed, my Invention of "IMPROVEMENTS IN WEIGHING MACHINES;" in which
said Letters Patent is contained a proviso that I, the said Mark Free-
man, shall cause a particular description of, the nature of my said Inven-
tion, and in what manner the same is to be performed, to be inrolled.
in Her said Majesty's High Court of Chancery within six calendar months
next and immediately after the date of the said in part recited Letters Patent,
as in and by the same, reference being thereunto had, will more fully and
at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Mark Freeman, do hereby declare that the nature of my Invention, and
the manner in which the same is to be performed, are fully described and

page_text: to the Drawings hereunto annexed, and to the figures and letters marked
thereon (that is to say):-
My Invention relates,-
First, to a mode of constructing weighing machines for weighing letters
and other articles.
And, secondly, to a mode of constructing weighing machines suitable for
analytical and other purposes, where exceedingly minute matters are to be
weighed.
And, in order that my Invention may be fully understood and readily
carried into effect, I will proceed to describe the Drawings hereunto annexed,
and the figures and letters marked thereon.
DESCRIPTION OF THE DRAWINGS.
Figure 1 represents a side view, and Figure 2 an end view of a weighing
machine constructed according to my Invention, and is intended to weigh
letters; but such machines may be made suitable for weighing other articles,
by having a scale applied, in place of the hook shewn, in which the letter to
be weighed is placed. The peculiar character of this weighing machine is
tlie mode by which the beam is caused to take a new bearing or point of
suspension at each additional weight. a is the standard of the machine;
is a plate on which is marked the range of weights the machine is made
capable of indicating; c is a rod and pointer affixed to the bean d. This
Beam consists of the bar d, with a weight at one end, and a scale or book c,
suspended to the other end, as is shewn; and on the beam are affixed a series
of bars f, having at each end of their ends a knife edge, as is very clearly
shewn in the Drawing now under description. 9, 9, are two plates of steel
on which the knife edges rest as they come into action, and for the time being
act as the fulcrum on which the beam moves,. the beam will therefore be
seen to have several fulera which come into action according as the letter
or otlier article to be weighed is more or less heavy. h, h, are two side
plates of the framing, having knotches to guide the knife edges into their
position, and to prevent the beam being slided along the curved surfaces.
I would remark that it will be evident that the parts may be varied
without departing from this part of my Invention, which consists in so
arranging the beam that it may be able to vary its points of bearing to meet
the requirement of different weight by varying the lengths of leverage on
either side of the fulcrum which for the time being may have been acting to
support the beam.

page_text: I will now describe the second part of my Invention; and in order that the
object of this part of my improvements in weighing machines may be well
understood, I will first remark, that in weighing exceedingly minute quantities
of matter by the aid of scales, the scale beams are at all times suspended from
the middle of their lengths; or in other words, the leverage of a scale beam on
both sides of the fulcrum is equal; it consequently follows that in weighing any
matters the weights used in the scale must be equal to the matter weighted,
which renders the formation of exceedingly minute weights necessary, some
requiring a magnifying glass to ascertain their size, and to enable the person'
using such weights to move them into and out of the scale; and, in addition
to the trouble and difficulty thus experienced, there is great difficulty in
making such weights correct; and, further, notwithstanding the smallest weights
for such purposes are made of platina wire, the chemist often is unable to
carry his experimental enquiry to the extent desired, owing to his being
unable to obtain correct weights of still less weight than those now made.
Now, the second part of my Invention relates to suspending scales from' a
scale beam in such manner that the leverage of the end of the beam on'
which the scale to receive the matter to be weighted shall be considerably
greater than the leverage of the end of the beam from which the scale is
suspended which receives the weights, by which means the matter weighed
will only be a known proportion of the weight used when the scale beam is
brought to a state of equilibrum, in place of the matter weighed being equal
to the weight employed, as heretofore. By this means weighing for analytical
and other purposes may be carried to a greater extent, without having weights
so small as now in use; but by using such small weights as are at present
employed, the weighing of the most minute quantities of matter may be
performed. Thus, supposing the leverage of the beam to which the weighing
scale as suspended be as five, ten, twenty, or thirty to one, the same weights
now employed would enable the operator to weigh matters of a fifth, a tenth,
a twentieth, or a thirtieth the weight which he is now enabled to weigh, and
with the same facility in respect to the weight which he is now enabled to
do when weighing matters only equal to the weights employed.
Figure 3 shows the side view of a weighing machine constructed according
to this part of my Invention; A, being the scale beam; B the fulcrum or
the knife edges on which the beam is suspended; C is the scale for receiving
the weights; and D is the scale for receiving the matter to be weighed; and
the leverage is made as ten to one; consequently, the matter weighed will be
only one tenth of the weight used in the scale C. I would remark, that the
relative leverage of the two ends of the beam beyond the fulcrum may_be

page_text: varied, depending on the result desired; but the longer leverage should be a
multiple of the shorter leverage, in order quickly to ascertain and note the
weight of the matter, put into the scale D.
4.
1.
Having thus described the nature of my Invention, I would have it under-
stood that what I claim is,.
First, the mode of constructing weighing machines as described in respect
to Figures 1 and 2:
And, secondly, I claim the mode of constructing weighing machines as
described in respect to. Figure 3.
In, witness, whereof, I, the said Mark Freeman, have hereunto set my
hand and seal, this Ninth day of March; One thousand eight hun-
dred and forty-one: --
MARK (L.S.) FREEMAN..
AND BE IT REMEMBERED, that on the Ninth day of March, in
the year of our Lord 1841, the aforesaid Mark Freeman came before our
said. Lady the Queen in Her Chancery, and acknowledged the Specifi-
cation aforesaid, and all and every thing therein contained and specified, in
form above written. And also the Specification-aforesaid-was-stamped ac-.
cording to the tenor of the Statute made for that purpose.
Inrolled the Tenth day of March, in the year of our. Lord One thousand
eight hundred and forty-one.