CERTAIN IMPROVEMENTS IN STEAM FLOUR MILLS, WIND MILLS, AND WATER MILLS, PARTS OF WHICH ARE ALSO APPLICABLE TO OTHER USEFUL PURPOSES
Year: 1855

page_text: LETTERS PATENT to Henry Pratt, of the City of Worcester, Engineer,
for the Invention of CERTAIN IMPROVEMENTS IN STEAM FLOUR MILLS,
WIND MILLS, AND WATER MILLS, PARTS OF WHICH ARE ALSO APPLICABLE TO
OTHER USEFUL PURPOSES."-Partly a communication from Edward Harrisou,
of Connecticut, United States of America.
Sealed the 10th January 1856, and dated the 11th July 1855.
PROVISIONAL SPECIFICATION left by the said Henry Pratt at the Office
of the Commissioners of Patents, with his Petition, on the 11th July
1855.
I, HENRY PRATT, of the City of Worcester, Engineer, do hereby declare
the nature of the said Invention for "CERTAIN IMPROVEMENTS IN STEAM FLOUR MILLS,
WIND MILLS, AND WATER MILLS, PARTS OF WHICH ARE ALSO APPLICABLE FOR OTHER
USEFUL PURPOSES," partly a communication from Edward Harrison, of Con-
necticut, in the United States of America,to be as follows, that is to say:-
I propose by my various improvements in flour mills to reduce the first
cost of erecting, and also the working expenses afterwards, with a greater
increase of product, and of superior quality to that usually obtained from
the same description of grain; and the main characteristic which dis-
tinguishes my self-acting flour mill, whether driven by steam, wind, or
water, is the introduction of a ventilating shaft in the centre of the build-
ing, by which a perfect system of ventilation and temperature is kept up,
so as to bring the grain and flour into a dry ripe state during the process
of manufacture, and to prevent that condensation and consequent

page_text: mildew, which at certain times of the year is so injurious by its tendency
to taint the whole product of the mill; and the manner in which I carry
out my various improvements may be stated under the following heads;-
Firstly, in my self-acting steam flour mills I combine the flues of the
chimney with the ventilating shaft, so constructing the flue at a conve
nient part that the heat arising from the fire or hot air passing up the
flue is given out, thus forming a self-acting kiln, and by conducting the
grain over screens and allowing it to fall into elevators until it becomes
thoroughly dry and ready for the process of grinding. The residue of
heat generated in the flue, as before described, is made available for
increasing the draft in those flues or compartments of the ventilating
shaft which are connected with the condenser of the steam engine, and a
powerful current of cold air is thus induced and made to re-act on the
large metallic surfaces of the condenser (which I use in connection with
my steam engine), the cooling influence of which condenses the steam
without the aid of cold water, and at certain periods of the year I can
apply the heat arising from the waste steam to keep up a proper tempera-
ture in the mill. There
may be
any number of compartments or flues in
the ventilating shaft, but for a double self-acting steam flour mill I prefer
six, namely, two for the boilers, two for the condensers, and two for the
mill purposes, all under regulations. The exhausted steam from the
engine is conducted into the condenser, which is a plain spacious cylin-
drical receiver or receivers of wrought iron, through which a number of
cast-iron air pipes pass in an horizontal position. This causes the con-
densed water to drop from pipe to pipe, and may be likened to rain, con-
tinually presenting a large surface of water to the exhaust steam. The
air pump is of the ordinary construction and size, but the mode of driving
it is both novel and convenient, namely, by an adjustable pin secured on
to the main driving wheel. By this mode of forming a vacuum, the air
pump is not hampered with the cold water for condensation, consc-
quently there is more vapour to heat thirty times less water, which causes
the distilled or condensed water to leave the air pump at nearly boiling
point. This hot water falls into a small receiver to which the hot water
pump is attached, which forces it up into another receiver placed a few
feet above the boilers, a float stone and other apparatus regulating the
supply. By this application I am enabled to use steam at a low heat, at
or a little above the pressure of the atmosphere, thus avoiding all risks of
explosions, and by using the condensed or distilled water over and over
again, the boilers are preserved from corrosion, which allows me to use
them of the most effective and economic form. In situations where water

page_text: cannot be procured, this discovery is invaluable. In the basement of the
building I fix the engines and condensers, preferring to use a separate
engine for each set of millstones. And in order to economise fuel, with
steam at a trifle above the pressure of the atmosphere, I place a cut-off
valve between the regulating throttle valve and pistons, and thus allow
the steam to expand into vapour before it is discharged into the con-
denser; and for the economy of room and to prevent the loss of heat by
radiation, I have a large store of heat concentrated in and by a fire-brick
bridge and stove within the interior of the boiler, the boiler being pro-
tected with a suitable jacket around on the exterior. This uniformity of
heat not only generates steam regularly, but is a main element to burn
the smoke. In tubular boilers upon which smoky coals act, the store of
heat consists partly of tubes of fire clay, or cylindrical hollow tiles of
irregular thicknesses, placed within the tubes of the boiler, so as to detain
and burn the smoke, the front of the boiler next the stove being pro-
tected with fire-brick work. But the form of boiler I use in connection
with my engines for the double self-acting steam flour mills is of an
upright cylindrical form, the inner plates being concentric with the out-
side, leaving a space between the inner and outer plates of about nine
inches, which distance is increased over the crown. By this form of
boiler I am enabled to set it immediately over the furnace or fire bars,
constructing a bridge at the back of fire, extending up in the hollow of
the boiler nearly to the crown of the inner plates; and such bridge being
made hollow, I am enabled to conduct a stream of air in from below the
furnace up the bridge and out at the top and back, to descend again with
the products of combustion into the chimney flues of the ventilating
shaft. Around the flues is a mass of fire brick, partly worked in with
fire clay and partly loose, with two air flues on each side under regula-
tion. The advantage I gain by this construction of boiler and furnace is
very great, as the whole heat given out by the combustion of the coal is
directed on the surface of the interior of the boiler and detained there,
so as to entirely consume the smoke arising therefrom. The floor above
the basement is occupied with the stones for grinding and my mode of
mounting such stones will be hereafter described under another head.
But one feature of novelty is the application of a ventilating shaft to carry
off the moisture arising from the meal, and to facilitate the current of
cold air through or between the stones. In order to carry out the pro-
gressive principle of grinding conveniently, I deliver the meal from each
large and small pair of stones into a double bolter and duster, which
is place on floor above the stones; and the novelty here is that of placing
and arranging two bolters and a duster in one case driven by one hand,

page_text: so as to ventilate and receive and deliver the flour and offals without the
aid of "hopper boys" or screws. In order to make the best work, flinty
and mild wheats are ground and dressed separately, and mixed with
unerring accuracy in the flour. For this operation the flour from each
mill is conducted on to a board, which is moveable at pleasure, so as to
deliver the mixed flour into either of the large hoppers, from which it
can be drawn out at pleasure. Another labour-saving machine, and
which I consider novel, is the combination of a metal hopper and valve
with a scale beam, for the double purpose of weighing the grain and
then delivering it into elevators.
Secondly, my improvements relate first to what may be called wind
mills, and consist in the use of wind, either as a direct means of power,
or as an auxiliary to steam power, and consist in the use of the current
induced by the central or ventilating shaft, which in this case must be
greatly enlarged, undivided, and circular, to make the force of the
current available as a motive power. In this arrangement I prefer fixing
the wind wheel on a vertical shaft outside the large central ventilating
shaft, fixed in such a manner that the current shall enter from the out-
side of the building through a funnel-formed airway, the impingement
being directed or the periphery of the wheel at right angles with its axis,
such wheel to be provided with a suitable regulator, and may or may not
be geared so as to work in connection with steam power, but in every
instance the axis of the wind wheel would form also the axis of the
grinding stones, and according to the extent of the requirement the
number of stones and wind wheels should be increased with the building,
which would be circular and fire-proof; the hollow shaft to be carried a
sufficient height, and capped with an open roof or umbrella, so contrived
as to prevent the action of high winds being opposed to the upward
current For agricultural purposes, where the first cost is an object of
consideration, I construct a common post wind mill, which is made to turn
round so as to cause the funnel-formed airway to face the wind, and thus
to direct the force on to the spiral vanes of the wheel, which is placed
in the centre of the mill, and from which all the movements of the mill
are put in motion without the-aid-of-cog-wheels.
Thirdly, relates to the application of water power applied direct on the
spindle or axis of the millstone, as also in the mode of transferring the
power required for all other operations necessary, so as to avoid cog
wheels and the vertical water wheels. And before proceeding to describe
the last part of my improvement in mills, I will observe that the mode
of condensing steam and forming a vacuum, the assistance of a central
ventilating shaft, the power or auxiliary power obtained by the wind

page_text: wheels, as herein-before described, are applicable to many other descrip-
tion of mill operations, rendering such buildings much more healthy for
the operatives, as well as to greatly economise their cost for the power
required.
Lastly, my improvements relate to the mode of mounting the mill-
stones; and this portion has been communicated to me by Mr. Edward
Harrison, of Connecticut, United States of America, he having obtained
a Patent in that country for his Invention, and consists in the use of a
suitable iron casing, in the inside or crown of which is fixed the stationary
top stone, the running stone being under, and fitted by means of a
metal back and hub secured to the centre shaft, moving freely within
the case, which case is supported on suitable uprights, leaving sufficient
room below, that a pulley, bevel, or other wheel may be placed on the
shaft to which the running stone is fixed, in order that it may be put in
motion by the power derived from steam, water or wind, or a combina-
tion of all or any of them.
Another feature of improvement consists in connecting the driving
shaft with the shaft on which the stone runs in such a manner that spring
bearings may be introduced; by this means a kind of elastic pressure is
given out between the stones while grinding. But suppose such stone to
be driven by gearing or bands, then I use a boss or socket for the shaft
to rest on, such boss or socket to rest on suitable springs, so as to obtain
SPECIFICATION in pursuance of the conditions of the Letters l'atent,
filed by the said Henry Pratt in the Great Seal Patent Office on the
10th January 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
PRATT, of the City of Worcester, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eleventh day of July, in the year of our Lord
One thousand eight hundred and fifty-five, in the nineteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Henry Pratt, Her special license that I, the said Henry
Pratt, my exccutors, administrators, and assigns, or such others as I,
the said Henry Pratt, 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
Channel Islands,
Islands, and Isle

page_text: of Man, an Invention for "CERTAIN IMPROVEMENTS IN STEAM FLOUR MILLS.
WIND MILLS, AND WATER MILLS. PARTS OF WHICH ARE ALSO APPLICABLE TO OTHER
USEFUL PURPOSES," upon the condition (amongst others) that I, the said Henry
Pratt, by an instrument in writing under my hand and seal, should parti-
cularly 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 Henry Pratt, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the follow-
ing statement (that is to say):-
In my Provisional Specification I have fully stated the purpose and
object of my various improvements in mills; but in order that they may
be more readily understood, I have exhibited my various improvements
in the Drawings hereunto annexed, which I will proceed to describe.
DESCRIPTION OF DRAWINGS.
Figure 1, Sheet One, represents a front elevation of a double steam
flour mill, shewing the ventilating shaft carried up much beyond the
roof. This elevation is given for no particular locality, but a situation
should of course be chosen easy of access by canal, railway, or other road.
Figure 2 is an end view of the same, shewing the openings M in the
ventilating shaft above the roof; as also a number of small openings for
the purpose of general ventilation, marked A, A, &c., as well as the air-
ways B, B, for the air-surface condensers; Figure 3 is a sectional plan of
the elevation (Figure One) taken through C, C, exhibiting the divisions
of the ventilating shaft, and a top view of the engine boilers D, D, the
flues in connection with which are marked E, E; Figure 4 is a sectional
plan, taken through F, F, of the elevation, Figure One; Figure 5 is also
a sectional plan, taken through G, G, of the elevation, Figure One;
Figure 6 is likewise a sectional plan of the elevation (Figure One), taken
through H, H; Figure 7 is a vertical section of Figure One, taken through
I, I, of the plans; and Figure 8 is a transverse sectional view, taken
through J, J, of the plans.
Having thus defined the several sections, I will observe that each part
requiring description is defined with the same letter of reference as they
appear in the various views, and this description only relates to the novel
and important parts in which my Invention consists, not forgetting that
the entire arrangement conduces to the realization of my system, but

page_text: which of course may be greatly modified to suit locality or circumstances;
as, for instance, the same principles and advantages may be applied to a
single mill or to any number of double mills combined in one establish-
ment. I mean by the term double mills, the application of two
separate steam engines and two separate sets of mill apparatus. In the
back part of the basement of my building I place the engines K, K, with
their boilers D, D, avoiding the placing of a floor over this part, as will
be seen by referring to plan Figure Three, and transverse section Figure
Eight, while the front part of the basement is occupied with the con-
densers L, L, L, L, shewn in top views by dotted lines at Figure Three,
and in side and end views at Figures Seven and Eight; and it will be seen
that the airways B, B, Figure Two, (represented by the same letter as
dotted through the end walis at Figures Seven,) are immediately opposite
the condensers; and as the condensers are constructed in the form of a
boiler, having a large number of air-tight tubes running through them
from end to end, it is evident that the heat of the waste steam being trans-
ferred to the air through the pipes, together with the heat of the chimney
flue, and the great height of the ventilating shaft, a strong upward
current is induced first in through the airways B, B, then through the
tubes of the condensers to the flues M, M, of the ventilating shaft, as
indicated by the arrows B, B, B, B, and M, M, Figure Three. The
divisions of the ventilating shaft marked T, T, are for the general ventila-
tion of the mill, the cold or heated air entering near the floors and
ultimately passing into these compartments under the roof, but not shewn
in the Drawing. In a general way I prefer auxiliary flues placed around
the ventilating shaft, four and a half inches square, similar to the cellular
wall which forms the kiln, hereafter explained; but in winter, when the
warm air from the air surface condensers is required to elevate the
temperature of the mill and granary, the vanes, shewn by dotted lines,
and marked I' in Figure Six, are shut, and the door above the vanes in
the ridge of the roof is opened, which allows the air surcharged with
vapour in its passage through the different compartments to enter the
ventilating shaft through the opening H'; and as the roof is planked and
lathed, and covered with tiles or slates, no condensation will take place in
winter, and no inconvenient heat in summer. The rafters are con-
sequently dispensed with, as will be seen by reference to the Drawings.
This vapourised or moist air is attracted by the small warm ventilating
flues formed in the walls of the ventilating shaft, or caused to pass
through wooden trunks situated in any part of the building, neither of
which are shewn in the Drawings.
In this Figure I have exhibited in a top view the hoppers and scales

page_text: O, O, for weighing the corn, from whence it is taken up by the elevators,
shewn at Q, Q, Figure Seven, and conveyed on to any of the desired
floors by spouts or conductors in the usual way; R, R, are top edge views
of the driving wheels, deriving their power direct from the crank shaft of
the engine, which, being geared into a corresponding bevil pinion, at
once produces the vertical action required, from which the millstones
N, N, are simply driven by bands.
The next floor, Figure Four, exhibits the position of the small and
larger pairs of stones, marked N, N, and denoted by the same letters of
reference in the elevations, Figures Seven and Eight; and in this floor
will be seen the elevators Q, Q, in section, as also the weighing apparatus
O, O, in plan; S, S, being trap-doors in the various floors for the sacks
to pass up; and U, U, are double elevators for taking the meal to the
bolts above; and V, V, are hoppers or bins for receiving the flour after the
necessary bolting, which hoppers or bins are entered from the floor above,
delivering the flour to the floor below, where it is at once sacked and
weighed on the weighing hoppers close to.
In the sectional plan, Figure Five, are seen the elevators Q, Q; as also
the double meal elevators U, U, with the traps for the sacks, as described
in the last Figure; as well as the garners W, W, W, W, and the upright
wood shaft X, X, shewn in section. I may add, this wooden shaft is
represented in Figures Seven and Eight denoted by the same letter of
reference, and gives motion to the sack, tackles, elevators, bolts, and
other mill apparatus situated on the floor, Figure Six, not distinctly
shewn.
I will now explain an important feature of my Invention, namely, the
preparing of the grain for grinding by the self-acting kiln Y, the cellular
wall of the ventilating shaft being constantly heated by the heated air or
smoke that passes up through the flues. This heat is given out to the
grain passing down the cells or spouts, to be hereafter more fully
explained; and to facilitate the operation of drying and cooling, I place
in the chambers Y, Y, in the sectional plans, Figures Five and Six, a
series of inclined wire-work screens that the corn may fall and slide-off-
from one to the other, and-which-inclined screens are exhibited in dotted
lines at the same letter in Figure Eight. Thus the corn is thoroughly
dried, cooled, and prepared for grinding, and is gradually raised by the
elevators from the kilns Y, Y, and passed through again and again if
necessary, and then conveyed to the smaller garners W, W, from whence
it is conducted through the small openings in the garners, or through
the hoppers Z, Z, and from thence to the stones for grinding.
In Figure Six will be seen the termination of the double meal elevators

page_text: U, U, and the elevators Q. Q, which terminate over a pulley in the roof,
as seen at Figure Seven. The large pullies A', A', are drawn on this
floor to shew that they may be made subservient to the driving of three
pair of smaller stones from each shaft, as here exhibited.
Having thus gone through my general arrangement as applicable to
steam flour mills, I will proceed to describe Sheet Two, which exhibits
on a larger scale the steam engine and air-surface condenser and the
boiler I propose using.
Figure Nine represents a vertical view of my steam engine and air-
surface condenser; A, A, being the basement; B, B, the warehouse floor
of the mill; and C, C, the grinding floor. Figure Ten represents a top
view of the condensers and horizontal section of the stationary parts of
the engine. D is the cylinder of the engine, fitted with angle parts E
and E'; the latter parts extend up to form a bearing for the driving shaft.
F is a top plate connecting the four angle parts together, and fitted with
an upper stuffing box G, through which the piston rod H works, prefer-
ring this arrangement for obtaining parallel motion; I, I, is an iron rod,
secured to the standard E, passing through the tubular stay piece J and
through the wall K, to which it is secured by means of a washer and
burr; the fly wheel L, and eccentrics M, N, and O, for working the cut-
off and slide valves, as also the force pumps, which with their attendant
parts, will explain themselves; P, P, is a driving wheel fixed to the main
shaft, giving motion to the pinion Q, which is fixed to the vertical shaft,
for giving motion to the stones above, and which shaft rests and works
on a boss, shewn in dotted lines at S, and is supported by the straps, R, R,
being bolted to the joist of the mill floor; T is the piston rod of the air
pump; and T the adjustable connecting rod, having a free action at
U, U, where it is connected to the piston rod T by a pin in the usual
way; but as great exactness is required in the length of the stroke for the
air pump, and as it may be economical to lessen the stroke in cold
weather, I have found it necessary to introduce the double screw and
socket V. by which means the length of the stroke may be altered and
easily adjusted, the same principle being applied to the force pumps and
cut-off valves. The connecting rod T¹ is united to an adjustable pro-
jecting pin W, fixed as much out of the centre of the driving wheel as
may be necessary for giving the required stroke to the piston of the air
pump. X and X' represents an end view of the air-surface condenser.
also exhibited in a top view at Figure Ten, marked with the same letter.
but partly broken off for the convenience of space. The manner in
which I form this air-surface condenser will be understood by the follow-
ing description:-The outer case is formed cylindrical and of boiler

page_text: plate, constructed with projecting flanges at each end, to which the cast-
iron end plates are secured by copper rivets in the usual manner, the
ends being cast with large and small holes regularly placed, through
which I insert as many tubes of cast and wrought iron; and I make such
cast-iron tubes sufficiently small, that when inserted in the end plates.
a space shall be left around to be filled up with suitable cement, which
must be done with great care to prevent leakage; at X', I have repre-
sented one part of the end removed for the purpose of exhibiting the
interior of the condenser. Y, Y, is the outer wall of the building, and
immediately opposite the condenser are placed two open gratings Z, Z,
to admit in cold air.
Having thus described the several parts of my engine and air-surface
condenser, in the same position and order as represented on a smaller
scale in Sheet One, I will now proceed to describe its mode of action
when in use.
a, Figure Ten, is the steam pipe fitted with the usual throttle valve.
not shewn; and b, the piston rod of the cut-off valve worked by the
eccentric M; c is the piston rod of the slide valve; and d, d, the piston
rods of the force pumps, two being shewn for the convenience of alternate
repair, and for the purpose of forcing hot or cold water to any part of
the building. The exhaust steam passes away through the tubes e, e, e.
entering the condenser X' about the middle, which after filling the first
cylinder passes to the second one through the connecting pipe f. f, as
shewn by the arrows. This steam is rapidly condensed by its contact
with the surfaces of the tubes, which are kept cold by the great draft
of cold air passing through them from the outer grating, before referred
to at Figure Three, Sheet One. The effect of presenting a surface of
iron equal to about 2,500 feet, or 100 feet for each horse power, obtained
by this tubular principle, will have the effect of rapidly condensing the
steam, which will hang and drop from tube to tube until it falls into the
exhaust pipe g.., which is connected with the air pump, and through
which this condensed steam and vapour passes into the air pump at each
successive stroke, the vapour and water being forced-by- the upward
stroke of the piston-into a reservoir with a valve attached, and from
thence it is conducted through the oval tube h, Figure Ten, to the force
pumps below, to be pumped up to a reservoir situated a few feet above
the boiler, from which it flows back again at a high temperature into the
boiler merely by its gravitating power, the supply being regulated by a
float stone or other apparatus, thus securing great economy of water and
fuel, in addition to which no corrosion nor blow-up will take place in
the boiler.

page_text: Before proceeding further, I will observe that I do not confine myself
to the circular form of tubes to be used in the air-surface condensers, for
they may be square or hexagon, or any other suitable form.
Figure Eleven represents a front view of the engine and fire-hole and
vertical section of the boiler, but which should be clothed around with a
suitable jacket. The dead plate is composed of hollow bars extending
from h, h, and the doors of the fire I attach to rods, supported by pins
at the top end, secured to the joist above, which rods are represented
partly in dotted lines at ko, k, k, k, the right-hand door being represented
open. In the middle of the fire doors I place at right angles a series of
wires, by which means the air is greatly divided and heated before
coming in contact with the fire, at the back of which I construct a fire-
brick bridge, extending up nearly to the inner crown of the boiler,
marked m, m, m, m; and in that part of the bridge immediately behind
the fire I construct an open airway, shown in dotted lines, the air enter-
ing at o, and escaping at the top and the back of the bridge; a trans-
verse section of which (with the airway) will be seen by referring to
Figure Twelve, which is a section of the boiler, bridge, and fire-place,
shewing the fire bars and dead plate, h, as also the side airways P, P,
the dotted circle Q, Q, representing the position of the steam box or
dome and its connection with the steam pipe, as shewn in the last Figure.
The further use of this arrangement and bridge I will describe by
another illustration on a subsequent Sheet; and before closing the
description of this Sheet, I will observe that I have marked the various
parts of the engine in these Figures with the same letters of reference
as they occur in Figures Nine and Ten.
Figure Thirteen, Sheet Three, represent a vertical section of the boiler
and boiler seat, taken through n, n, of Figure Twelve, Sheet Two, shew-
ing an edge view of the bridge m, m, as also the airways 0, 0, 0, 0, the
course or current of the flame being indicated by the arrows; and I will
now proceed to describe the general construction of this furnace, and
the benefit derived from the use of the bridge.
a, a, a, are three fire-clay bricks, long enough to rest on the brickwork
each side; on the top of which I place a plate of iron, having a flange
projecting downward on the front and back, marked b, b, clipping the
bricks, and on this plate the series of hollow bars rest, forming the dead
plate, marked h, shewn also in an end view at Figure Eleven, Sheet
Two, marked with the same letter; and c represents an edge view of the
fire door attached to the rod k, ; and d is a large fire-clay brick, of

page_text: sufficient size to form the side of the fire-hole; and e, e, and e¹ are three
bricks, long enough to rest on the side bricks d, the middlc one being
partly curved to correspond with the internal circular form of the boiler,
and the front brick e' is thinner than the others, as it helps to form a
seat for the boiler; is a brick, forming part of the side of the furnace,
resting on the set-off g, (marked by the same letter at Figure Twelve,
Sheet Two,) and on the inner brick e, leaving an opening underneath it
for the flame and heat to pass through, which opening 1 have marked as
extending from i to i; j, j, j, are the crown bricks, shewn in section, and
are long enough to rest on the side bricks /; and it will be seen that there
are openings between the three crown bricks to allow the heat and
flame to pass through, but which is broke and contracted by placing
loose fire bricks across the openings at short intervals.
The brickwork represented in section at ', ', is built across in front
of the crown of the furnace, with an occasional omission of bricks to
form airways, as shewn by the arrows. lis a side view of the fire bar,
shewn in a transverse section at Figure Fourteen, and drawn for the
purpose of shewing its sectional form, where it will be seen that it tapers
downward, in order that the cinders and clinkers may clear themselves
in falling through. The bridge m, m, extends nearly to the inner crown
of the boiler, and the airway up through it being exhibited, I will
explain that the bridge contracting the draftway in this position will
have the effect of impinging the volume of flame and smoke, which, in
connection with its supply of air, will greatly conduce to a perfect com-
bustion, igniting the smoke, and consuming the smaller particles, which
would otherwise, by the great current, pass off in an unconsumed state
or smoke. The dotted lines P, P, extending down transversely through
the boiler, simply denote the water, and the vertical rods q, q, q, perform
the double use, first, as stays for the inner and outer crowns of the boiler;
and, secondly, as electric rods when connected with the conducting
rod r, r.
I do not confine myself to use the particular shaped boiler here
described, as a tubular boiler may in some instances be preferred; but
in that case-I-prefer inserting in the metal tubes a loose tube of fire clay,
formed in several parts, simply pushed into the tube, but every alternate
piece of such fire clay tube I prefer to be of a larger or smaller bore.
in order that at each contraction the current of the flame shall be
impinged, causing the current to vibrate in its course.
These inner fire-clay tubes must fit loose, and leave plenty of room
for expansion and contraction. I conceive this addition of inner fire-
clay tubes to be of great importance to tubular boilers, as, from the

page_text: great heat the fire clay will retain, it is evident that any unconsumed
particles of coal escaping into the Hues, they will be there consumed by
the vibrating action of the heat, allowing no smoke whatever to escape,
independent of which sufficient heat would be retained in the flues to
counteract the sudden rush of cold air during the process of firing.
At Figure Fifteen I have represented a sectional view of a boiler tube,
broken off for the convenience of space; and it will be seen that I have
represented that part of the fire clay inner tube that would be placed
in front of the boiler or in connection with the fire box with a projecting
flange, that when the whole series are placed in, they will form squares
of fire clay on the front of the boiler, with the heat passing through their
tubular centres. This fire-clay tube I have marked a, and represented
it in an end view at Figure Sixteen; and the last fire-clay inner tube, or
the one marked B, placed at the extreme end of the boiler, is squeezed
inward when the fire clay is in a plastic state, for the purpose of further
impinging the heat and flame before it passes away to the chimney or
stack. This tubular brick I have also shewn in and end view at Figure
Seventeen. This same principle is also applicable, though for an
entirely different purpose, to my system of condensation, as heretofore
explained, and exhibited in Sheets One and Two.
In the tubes of the condenser I place, say, at the middle and back
end, a small piece of thin iron, or any other suitable material, standing
up in a vertical position, filling up about one-half of the transverse
capacity of the tube; the effect of which will be, that the cold air in
passing through the tubes will be intercepted in its course, causing a
vibratory action round or against the tubes, exercising its cooling
influence on their surfaces, and passing off at a higher temperature by
the contact, in order for the fresh and continuous cold current to per-
form the like office. But with a view to be thoroughly understood in
this particular, I have thought it necessary to exhibit this on a large
scale, which I have done among the details at Figures Eighteen, Sheet
Three. c, c, and c, c, represents a longitudinal section of a condensing
tube, drawn about half size, and broken off at c', c', for the convenience
of space; and d is a piece of wire or tubing, having a piece of tin or sheet
iron e and e' secured at the ends. I prefer this, being the most simple
and economic, and will produce the effect we desire, namely, by break-
ing the current, as indicated by the direction of the arrows.
Figure Nineteen represents a transverse section of the tube last
described, as also the part e¹, the connecting tube or part & being shewn
by the dotted circle.
In Sheet One I have represented my improved mode of weighing in

page_text: and weighing out the produce of the mill; but considering this somewhat
important; have thought it proper to exhibit it on a larger scale, and
which will be seen at Figure Twenty, Sheet Three. a, a, is the grinding
floor; and b, b, the warehouse floor; c, c, is the joist, to which is suspended
the scale beam by the rod e; g, g, is a sectional view of the weighing
hopper, made of tin, to which are attached at the top edge the connect-
ing rods h, h, h, meeting at the top, and connected by a ring and hook to
the beam. The floor b, b, has a square hole cut through it for receiving
the hopper, and which hole must be of sufficient size to allow free
and perfect action to the apparatus, and according to the position of
the ball j, for giving the desired weight; and that weight in corn or grain
being poured into the hopper g, g, it will descend, indicating the desired
quantity, which is then liberated by opening the valve h. This is easily
done by means of the string or wire attached to it. The corn or grain
descending from the hopper is then conducted by the spout to a proper
receiver to be carried up by elevators in the usual way. This same mode
entirely applies to the weighing apparatus on the floor above. When
sacks are required to be weighed, I place a temporary floor or board on
to the top of the hopper, upon which the sack is placed and weighed in
the usual way.
Figure Twenty-one is simply a top view of the hopper g, y, shewing the
position of the rods h, h, h, and the cross bar m, m, which forms a guide
for the valve h.
In my Provisional Specification I have spoken of economy in the mode
of construction as a feature of novelty, and although the general
arrangement conduces to this, nevertheless I have considered it impor-
tant to shew how I construct my partition walls, and with the dimensions
of the bricks I propose using, which I believe to be novel and useful in
the construction of mills or other buildings. The walls I propose to be
six and a half inches thick, thus making the headers exactly that length,
and four and three-eights of an inch wide, and two and three quarter
inches thick; and the stretchers I make nine inches long by three and one-
sixteenth of an inch wide, and the same thickness-as-the-headers: namely;
two inches and three quarters; and at the top of such partition walls,
and where they key in with the outer walls just below the joists, as
shown on a small scale at Figure Twenty-two, I prefer spreading the
brickwork out, so as to shorten the bearings for the joists as much as
possible. And another feature of novelty in my partition walls is to so
form the bricks at certain places, that in working them up vertical
grooves shall be formed for the purpose of receiving wooden slides, by
which I divide or connect one garner with the other. These grooves

page_text: should be about an inch and three quarters square. But in order that
this part of my Invention may be thoroughly understood, I have
exhibited the bricks detached and built up, so that it may be seen how
they may be tied in one with the other.
a, Figure Twenty-three, represents a top view of a header; and b also
represents a header with the groove for receiving the wood slides; and
d, d, represents a top view of two stretchers, shewing the space between
them for the mortar, as also how they are shaped at e, e, to form the
groove, being ten and three quarter inches long to brick joint; and f is a
brick twelve inches long, to tie into the nine-inch wall, to form the three-
inch partitions of the cells or flues of the kiln; and g, a nine-inch brick
to break joint in the three-inch front wall, or to work up in a six and a
half inch wall as stretchers; and c is half a brick, especially required to
build up the three-inch partitions of the flues or cells.
し
Figure Twenty-four represents the head of a partition wall built with
the description of bricks last described, shewing how they are spread
out at the top for shortening the span or bearing of the joists h, h; j, j,
simply representing the floor of the mill in transverse section, exhibiting
the ploughed and tongued joint at /, l.
Another feature of my Invention, namely, that of drying, cleansing,
and preparing the grain for grinding, as before described, and exhibited
at a, a, Figure Five, Sheet One, may not be so intelligible as to be
readily understood; to obviate which I have thought it proper to exhibit
this spart drawn to a larger scale in a transverse section at Figure Twenty-
five, and a vertical section at Figure Twenty-six. E represents the flue
or hot-air passage in the main shaft, and on the outer side of which is
built a series of small vertical passages, formed by the bricks already
described, through which are inserted tubes made of tin, and roughed on
the outside, after the manner of common tin graters, such as ginger.
graters, etc. These tubes are smaller than the square of the passages,
for the purpose of allowing the corn or grain to fall from the granary
above through those passages; and in its passage it will be chafed and
cleaned by rubbing against the roughened tubes and the brickwork, of
which the passages are built; and as the brickwork will always be hot
from its proximity with the hot-air passage E of the ventilating shaft.
as seen in the various plans (Sheet One), the corn or grain may be thus
dried again and again, as this process can be carried on as long as may
be desirable by means of the elevator, shewn in transverse section at Q.
Another advantage derived from these circular graters is, that the
vapour as formed can escape through the small holes into the chimney-
like flue of the grater.

page_text: y is the ventilating, cooling, and evaporating part of the kiln, and
placed in this warm position to prevent condensation on the metal
screens, and to allow a current through them. The screens are not
for the purpose of sifting out impurities, but to expose and to conduct
the grain from the top of the mill to the hoppers below through a current,
as will be seen best in the vertical section, Figure Twenty-six; it is
evident, however, that some quantity of dirt and seeds may be secured
from the last screen and drawn off, as shewn in Figure Twenty-six.
These slanting wirework frames are shewn in a sectional end view at
a, a, a, b, b, represents the roughened tube placed in the passage e; and
d is a sliding stop, that can be pushed in or drawn out for the purpose of
opening or stopping the passage, which may be done simultaneously by
one stopper opening or closing the whole series.
Under the second head of my Provisional Specification I have also
described a particular description of building for mills, where the wind
is to be used as the principal or auxiliary power for working the stones.
etc.; and under the same head I have referred to what are called post
wind mills, and as I propose applying the wind power in the same way
as in the post wind mill, I have thought it necessary only to shew the
application thereof to a post wind mill, which I have fully represented
on Sheet Four, and which I will now proceed to describe.
Figure Twenty-six represents the windward side of the mill, this
direction being easily obtained, the whole mill working on a centre or
post, to be hereafter described. I have represented the whole structure
for lightness and economy as made of wood; and the top part from a, a,
to b, b, is slanted inwards, for the purpose of directing the current or
wind downward; and the space from c, c, to d, d, is also slanted inwards
for the same purpose, as also the side board e. leaving an opening for the
air to enter the mill from f. f. to f. f, which opening is supported by the
three upright stays g. 9. g. Figure Twenty-seven is an end view of the
same Figure Twenty-eight is a vertical section of Figure Twenty-seven,
taken through h, h; Figure Twenty-nine is also a vertical section, as
taken through i, i, in Figure 26; Figure Thirty is a transverse-section-of-
Figure Twenty-six, taken through j, j; Figure Thirty-one is a section of
the same description, taken through , k, of the same Figure; Figure
Thirty-two is likewise a transverse section, taken through 1, 1; Figure
Thirty-three is a like section, taken through m, m; the same lines of
dissection also apply to the end view, Figure Twenty-seven, in which
Figure 1 have marked them with the same letters.
Having thus defined the several plans and elevations, I will proceed to
describe the various parts; and in doing so I will use the same letter of

page_text: reference to denote the same parts as they occur in each Figure. The
base part of my mill is formed of a stout framing n, n, shewn in a top
view in dotted lines at Figure Thirty, strengthened by transverse stay
pieces, between which is secured four rollers, marked o, o, and through
the centre of which the post P is placed. This post must be firmly
secured in the ground, and to the traversing plate q, q, on which the
rollers o, o, work. Attached to the main frame n, n, is a long arm or
lever, to the end of which a cart wheel is placed, for the purpose of
assisting to turn the mill to take in the wind, or vice versa. This lever
also forms a main support. for carrying the stage or steps for entering
the mill.
The peculiarity of this construction of mill mainly consists in the mode
of collecting and transmitting the power of the wind to the uses of the
mill, and to this end, instead of using wind mill sails in the ordinary way,
I prefer collecting the wind into an hollow wheel, the axis of which forms
also the axis on which the stone works. This hollow wheel I have
exhibited in a side view S in Figure Twenty-eight, in a sectional view at
Figure Twenty-nine, and in a top view at Figure Thirty-two, the arrows
indicating the direction of the wind, first pressing against the windward
side of the mill, then passing in through the opening f. f, and up into the
wheel, which is an air-tight reservoir of power, consisting of the full
pressure of wind collected and pressed through the large central induc-
tion opening at the bottom of the wheel, which is seven times larger than
the four eduction vertical openings on the periphery formed by the sides
of the wheel, being contracted at s, t, s, t, etc.. Figure Thirty-two; these
spiral sides of the air reservoir being in reality vanes against which the
wind presses and escapes through the openings, as shewn by the arrows
the particular angle given to the sides regulating the velocity, as in wind
mill sails or turbines, of which this is similar in construction, the one
being actuated by a pressure of water and the other by a pressure of air.
The reservoir wheel S. as a matter of course, is pushed round in a
contrary direction to the flights of arrows. The advantages of this plan
over that of the ordinary wind mill are very great, as the whole power
of the wind acts upon the periphery of the wheel, or, by comparison, on
the extreme end of the wind mill sails, by which means I am enabled to
fix the millstone on the same shaft or axis, thus doing away with much
costly gear, and avoiding those dangerous strains common to wind mills.
And it will be seen in the elevation, Figure Twenty-eight, and trans-
verse section, Figure Thirty-three, that I have applied the progressive
system of grinding corn by exhibiting a large and a small pair of stones.
the smaller pair, sack tackle, and other moving parts of the mill being
worked from bands taken off from a pulley placed on the first shaft or

page_text: millstone spindle. I have not thought it necessary to describe every
particular part exhibited in this wind mill, as they are of minor impor-
tance, such as the position of the stairs and other parts, as the mill is
capable of modification.
The manner in which I apply the outer boards may be somewhat novel,
as I propose to fix them in double thicknesses, with butt points and
sheets of pitched paper placed between them, which will have the effect
of keeping the mill weather-proof at all seasons of the year, the roof
being slated or shingled. The basement of the mill may be fitted up for
a dwelling, when it is desirable to make such mill of large dimensions,
for the purposes of irrigation or other operations.
In my improvements in mill operations, mentioned in my Provisional
Specification under the third head, I refer to a mode of applying or
using water as a main or auxiliary power for driving millstones, the
power being applied direct on to the main vertical shaft on which the
large stone works, and this I have illustrated in four different. Figures
on Sheet Five, and may be defined as an improved turbine.
Before proceeding to describe these Figures in detail, I will observe
that for years past it has been considered by many eminent mathema-
ticians that water wheels on the principle of Baker's mill ought to give
out more power than any of the common water wheels; and of late a
variety of plans have been carried into effect with more or less success,
although few of them have had regard to the one essential property,
viz., that of proportioning the induction or supply pipe of the wheel to
the eduction openings on the periphery, and of regulating the velocity of
the wheel accordingly, so as to have the whole force of the water within
the wheel.
Figure Thirty-four represents a side elevation with the shaft A broken
off, which otherwise would be carried up through the basement floor to
receive the millstones; Figure Thirty-five is a top view, shewing the shaft
A in section, and plan of the wheel, shewing the position of the four
eduction openings e, f, g, h; e being shewn in its vertical form in the
top Figure. The induction pipe is made of iron cast in two parts, united
by screws passing through the side flanges i. i, etc., and assumes a
circular form at the mouth from j-to-j,-and-an-oval form from to; the
casting forming this induction pipe forms a semi-cylinder or drum for the
hollow shaft of the wheel to work in. extending back to 1, 1, and is cast in
such a way that the two uprights M, M', and the one in the same position
on the other side, shall form a rest or bed for it, and to which it is secured
by the screws n and n, partly shewn in dotted lines, a felt or other suit-
able packing being placed between the flanges for the purpose of making
them water-tight.

page_text: The wheel P is formed of sheet iron, rivetted together in the manner
in which steam boilers are generally made, secured to a cast-iron boss q
at the top for receiving the shaft A, and which casting also forms the
hollow shaft for receiving the water from the induction pipe in its way to
the eduction openings, before described, and extends down to r, where
it rests on the metallic bearing s, which is bedded on an elastic pack-
ing, for which purpose india-rubber would answer well; this packing I
have marked t. U is a strong iron arm, working on a pin or fulcrum at,
secured by the nut on which the latter is placed. Near to the end of the
arm is a cross piece or arm, marked w, working on an axis at its reverse
end, and through the slot y, y; and secured to this arm or cross piece is
the vertical rod a, a, by which means the hollow shaft, wheel, and stone
is depressed or elevated, for the purpose of insuring the desirable adjust-
ment of the stones one with the other; the small arrows simply indicate
the flow of water, and the large arrows the direction in which the wheel
is supposed to be moving.
Figure Thirty-six is a vertical section of Figure Thirty-five, takon
through the dotted lines c and d, all the parts of which are marked with
the same letters as in the last Figure; and in this view I am enabled to
shew how the water passes from the induction pipe j, j, through the
openings a, b, and c', in the hollow cylinder, and through the openings
d and e' to the wheel, escaping according to the height or weight of fall
through the openings e, g, etc., on the periphery, its course being best
defined by the arrows; and this view also exhibits, in section, the exact
form of the hollow shaft, shewing that the foot is concaved, and rests
on a convexed disc of metal, marked z. And in this view I am also able
to shew at a, a, b, the metallic rings secured to the hollow shaft,
and which rings are turned and fitted in the flanges c", e", and ", d",
the opening e", e", being filled up with a suitable packing to prevent
leakage, as this forms the collar for the working surfaces in which the
hollow shafts work, forming the axis of the wheel.
Figure Thirty-seven exhibits the lower casting of the induction pipe
and semi-cylinder, and sectional view of the hollow shaft, as taken
through a and b of the top Figure, shewing the manner in which the
water is screwed or pumped into the hollow shaft through the openings
a, b, c, and c, and also the four pieces of metal supports, indicated
by dotted lines, and marked 1, 2, 3, and 4, the shape of which represents
the manner in which the water is screwed out of the hollow shaft into
the body of the wheel, the parts that are seen being marked with the
same letters that indicate them in the other Figures.
Before closing this description I will observe that the outside of the
wheel p, as will be seen by referring to Figure Thirty-five, is divided

page_text: into four parts, inclining spirally towards the centre, an high or low
velocity being obtained according to the acuteness or obtuseness of the
spiral; the more acute the higher the velocity, the more obtuse the slower
the velocity, as in wind mill sails.
Flour mills worked by this kind of wheel will comparatively require
no gearing, as the size and speed of the millstone can be suited to the fall
and velocity of the water, the remnant of power being taken off by bands,
as described in the post wind mill, thus reducing the friction to a mere
nominal amount, leaving the power of the water to be used for the
direct requirements of the mill. This wheel, or mode of applying water
power, is especially applicable to high falls, and to all machinery where
a quick motion is required; but for very low falls, where the undershot
wheel is now used, it would be necessary to increase the diameter of the
wheel, and dispense with the stuffing boxes somewhat similar to the
wheel already described in the post wind mill.
And the last part of my improvements relate to a mode of mounting
millstones; and this part has been communicated to me by Mr. Edward
Harrison, of Connecticut, in the United States of America, he having
obtained a Patent for his Invention in that country last year, and which
will be understood by the following description and reference to the
Drawings exhibited on Sheet Six:-
Figure Thirty-eight is a side view of his improved mill; and Figure
Thirty-nine, a vertical section of the same, which I will proceed to
describe, using his own language. He says, "I construct my improved
grinding mill wholly of stone and metal, and in the strongest and most
compact manner.
Matched casings A and B receive the stationary and grinding stone;
the lower casting B has three columns H, descending from its under side,
upon which the mill rests, which columns are connected with each other
at their lower ends by the triangular base I, as shewn in Figure Thirty-
nine.
Three standards M and M', etc., rise from the upper casing A, and
support the hopper K, sockets J, J, etc. being cast on the under side of
the hopper to receive the top ends of the standards M, as will be referred
to hereafter-in-a-separate-Figure; the shoe I. is supported and vibrated in
the following manner, as will be best understood by referring to the
section, Figure Thirty-nine-A smooth vertical hole is formed in the
end of the shoe at ', which receives the standard M': a slot is formed
in the under side of the shoc at h, which receives into it the eccentric
pivot i. formed out of the top of the shaft C; and it will be evident that
as the shaft C revolves, a vibrating motion will be given to the shoe L,
working, as it does, loosely on the standard M'.

page_text: The discharge of the grain from the hopper into the shoe is governed
by varying the size of its discharging aperture T, by means of the sliding
regulator t, t, the grain falling in the direction of the arrows from the
hopper into the open end of the shoe, and into the aperture U in the
upper casing, and from thence it passes down the inclined passage V into
the chamber formed in the centre or eye of the upper or fixed stone E, E,
which is cemented and firmly secured within the upper casing A.
The lower stone or runner F, F, is formed of a united metallic back D
and hub W, combined with a disc face, composed of the requisite quantity
and quality of stone. The said back and hub of the runner may be formed
of soft metal, and be cast upon the back and in the eye forming the hub;
or may be formed of cast iron, and the stone be fitted and cemented to
the back and the hub. A broad metallic band a' embraces and unites
the periphery of the metallic back and the stone F, and as the face of
the stone wears away, the band is driven down, and may project below
the under side of the said back.
The shaft C is provided with three working bearings, which may be
variously constructed to meet the wear incident on a continuous action,
as it is of the highest importance that the shaft C should always maintain
a positive vertical position in order to insure that indispensable accuracy
in the grinding surfaces of the stones.
In the Drawings I have simply exhibited the top bearing A' formed
and accurately turned through a boss formed in the centre of the top
casing A, and the middle bearing B' is formed in the same way in the
lower casing B, which bosses may be so formed as to allow them to be
bushed with brass or any other suitable metal or metallic compound.
I give to the shaft C a vertical, elastic, and adjustable bearing by
means of the following arrangement, viz. The step G of the shaft passes
down through a hole in the centre of the base 1, and has a screw cut
upon its periphery, which is embraced by the supporting and adjusting
nut N; to the under side of the respective arms I, etc. of the base, there
are secured the springs g, g, g, by means of the sustaining and adjustable
screw bolts f,, etc., which pass up through the said arms of the base.
On the inner end of each spring g a rod e' rests, and rises through a hole
in the base near to the centre opening which receives the step G, and upon
the upper end of the said rods c¹, c', c', the nut a rests, as shewn in the
Drawings. The stiffness of the springs g., g. can be varied by means
of the screw bolts f, f, f, and the shaft C can be raised or lowered by
turning the nut N. The step G is prevented from turning with the nut
N by means of a longitudinal groove e in its side, and the screw d which
passes into the slot e, as shewn. But before concluding the description

page_text: of this Figure 1, will observe that the top and bottof casings A and B
are united by three strong bolts, of which one is only shewn in the section
marked 1', and the nut S; and Q is an iron pulley, fixed on the centre
shaft C, for the purpose of receiving a band, by which motion is given
to the runner or stone F.
Figure Forty is a view of the under side of the mill, reduced for the
convenience of space one half the size of the elevation and section, and
is drawn for the purpose of exhibiting the triangular arms I, I, I, the
springs g. g, g, bolt head /, /, /, shoe G, and the screw and head of the
screw d, with the lower side of the casing B, the nuts S, S. S, and ends
of the bolt P, P, P; as well as a bottom view of the fixed pulley Q, and
the opening R in the bottom case, through which the meal passes.
Figure Forty-one is a transverse section, taken through the dotted lines
Z, Z, showing a sectional view of the uprights M. M, M', and under side
of the shoe L, the hopper K being partly broken away for the conveni-
ence of space; the slot is also shown, in which the eccentric pin i of
the shaft C works; and the extent of the jiggling action imparted to the
shoe by the eccentricity of the pin is shewn by dotted lines, z, z.
Figure Forty-two is simply a top view of the shaft C and pin i.
Before closing the description of this mill I will refer to Figure Forty-
three, Sheet Three, which represents a top view of the runner or bottom
stone, shewing the furrows or radial airway grooves drawn to the centre,
one of which grooves is represented full size at Figure Forty-four, the
angular line shewing the outward termination of the groove, and the
dotted line the inward termination of the groove. The fine lines repre-
sent the cuts or cracks of the lower or running stone on the face or
between the airway grooves, before described, and the dotted lines
represent the cuts or cracks of the upper stationary stone, crossing cach
other at different degrees of angles,so as to increase or decrease the draft;
number 1 is the medium angle; number 2, the greatest draft, or most
obtuse angle; number 3, the least draft, or most acute angle.
The dotted lines also represent the position and direction of the
furrows or radial airway grooves in the top stationary stone, which
are not drawn to the centre, but are slightly eccentric, so that the furrows
when they cross and act upon each other will form an acute angle, and
create a centripetal action, which will tend to draw the coarser particles
on to the face of the stone where the cracks or cuts have a contrary or
centrifugal action, which will assist to throw out the meal when properly
ground, and not till then. This arrangement of cutting, combined with
the great velocity given to this mill, will cause a great current of air to
pass through the stones, and a large quantity to be ground.

page_text: The following are some of the advantages for constructing the runner
with a metallic back, combined with a stone grinding face, viz.:-The
stone grinding face of the runner can be worn nearly to its metallic back
with perfect safety, and when it is so much worn as to be unfit for use
it can be replaced at a comparatively small expense. Secondly, the
runner may be so rigidly and securely confined to the shaft, that when
placed in its metallic supporting frame the two stones can be accurately
faced by grinding them together. Thirdly, the large sized stones can
be with perfect safety used on this plan, as it admits of being rigidly
secured to the shaft, but which shaft must be of proportionate strength
to prevent any vibratory action.
Mr. Harrison also observes that metallic backs have been applied to
running millstones when the said millstone has been suspended upon a
bail and the grain fed through the eye of the same: and he also says
that a small-sized running millstone without a metallic back and eye has
been rigidly secured to its spindle, and therefore he does not set up a
claim for either of the said arrangements as his Invention, of course
referring to what had been done. in America. And I find also that a
Patent was granted, June the Fifth, One thousand eight hundred and
forty-nine, to George Hinton Bovill, for improvements in manufacturing
wheat and other grain into flour, wherein he described and claims a mode
of making the bed stone rotate instead of the top one, as had hitherto
been used.
But what I do claim as Mr. Harrison's Invention and my improvement
on the same is, that of forming the runner of a metallic back and hub,
combined with a disc grinding face composed of the requisite quantity
and quality of stone, the same being rigidly secured to the shaft by the
metallic hub of the runner when the said runner is arranged to operate
with the stationary uppermost stone, as herein described; as also the
mode of cutting the surfaces of millstones, as exhibited at Figure Forty-
three.
Secondly, I claim the mode of constructing and ventilating mills and
other such buildings as described and exhibited on Sheet One. without
regard to the particular form, shape, or proportion of the external wall
and central ventilating shaft.
Thirdly, I claim the general arrangement for preparing, drying, clean-
ing, and garnering grain for grinding, as exhibited on Sheet One.
Fourthly, I claim the mode of condensing steam as exhibited on Sheet
One, and on a larger scale on Sheet Two, without confining myself to any
form or shape of condenser or application thereof.
Fifthly, I claim the manner of varying and regulating the stroke of the

page_text: air pump in connection with the main driving wheel, as exhibited on
Sheets One and Two.
Sixthly. I claim the general construction of furnace and boiler with the
bars, dead plate, doors, etc., as exhibited at Figures Eleven, Twelve,
and Thirteen; as also the application of earthenware tiles to tubular
boilers, shewn at Figures Fifteen, Sixteen, and Seventeen,
Seventhly, I claim the combination of a double bolter and duster
driven by one band, as exhibited on Sheet One.
Eighthly, I claim the mode of weighing in or out the product of the
mill, as exhibited on a large scale on Sheet Three, Figures Twenty and
Twenty-one, and which mode of weighing is also applicable to granaries
and other purposes.
Ninthly, claim the application of the sizes and proportions of the
bricks for headers, stretchers, etc., as exhibited at Figures Twenty-two,
Twenty-three, and Twenty-four; as also the application of such bricks
to the building of thin walls generally, where economy, room, and
strength are objects sought after.
Tenthly, I claim the general construction of wind mills as exhibited
on Sheet Four, without confining myself to the general details thereon
exhibited.
Eleventhly, I claim also this wind mill, modified in combination with a
large central airway tower and fire-proof building, to which a bakery
may or may not be attached, the wind wheel either to be used separately
or conjointly with steam or water power.
Twelfthly, f claim the mode of applying water power to the driving of
millstones, grinding, or other purposes, as exhibited on Sheet Five. with-
out confining myself to the exact angle of the spiral sides of the wheel or
to the proportions of the other parts.
And, lastly, it is well known that cut-off valves have been used in com-
bination with high-pressure boilers; I do not claim any of these con-
trivances, however far the expansive principle may have been carried;
but what I do claim is, the combination of a cut-off valve with a low-
pressure steam engine boiler, so as to work at or near the pressure of the
atmosphere in the boiler, as exhibited at Figures Nine and Ten, Sheet
Two.
As witness this my hand and seal, this Seventh day of January. One
Witness,
J. S. COCKINGS, Patent Agent,
Birmingham