Improvements in or relating to Purifiers, Separators, and Graders.
Year: 1893

page_text: Date of Application, 2nd Dec., 1893
Complete Specification Left, 1st Sept., 1894-Accepted, 6th Oct., 1804
PROVISIONAL SPECIFICATION.
Improvements in or relating to Purifiers, Separators, and Graders.
A communication by DAVID J. DAVIDSON, STEPHEN G. MARTIN, and
ABRAHAM S. MARTIN, all of Port Huron, in the County of St. Clair and
State of Michigan, United States of America.
I, WILLIAM PHILLIPS THOMPSON F.C.S., M.I.M.E., of The Agency for
Foreign Patent Solicitors, 6 Lord Street, Liverpool and 6, Bank Street,
Manchester, both in the County of Lancaster and 323 High Holborn in
the County of Middlesex, Civil Engineer, do hereby declare the nature of this
invention to be as follows:-
The present invention has for its objects certain improvements in purifiers,
separators and graders adapted for purifying, separating and grading various kinds
of grain, seeds, middlings, flour and analogous substances which require to be
purified, separated and graded, and it aims at providing a machine for these
purposes of superior efficiency, economy and utility, one which shall dispense with
the complex mechanism, gearings and many other features heretofore common in
this class of machines, one which may be run with the least possible power, and
which shall take care of its own dust, and of the various other separations
which may be made thereby, each separation, being deposited and discharged by
itself.
The invention consists of the construction, combination and arrangement of
devices and appliances hereinafter specified.
The invention contemplates effecting the desired purification, separation and
grading of grain, seeds, middlings, flour and other substances by gravity in
combination with a continuous air current.
More particularly the invention relates to a horizontal purifier, grader and
separator, although the invention is not limited solely thereto, as the invention
contemplates a mechanism in whatever position it may be placed, and in whatever
form it may be made.
In carrying out the invention a continuous air-trunk or tube is provided, also
separating devices, and means to effect a continuous air circulation in said air tube
or trunk, the stock being fed into said trunk, the device being provided with
suitable discharge outlets and means of controlling the same.
The air trunk may be elongated horizontally, the trunk being provided with an
upper leg or portion and a lower leg or portion, the one leading into the other at
one side of the machine, and both legs communicating with the interior of the fan
case, provided with a suitable fan to effect a continuous circulation of air within
said trunk.
The two legs form one continuous air trunk or tube, leading from the fan case
back thereto.
The invention is not limited solely to the form or shape or position of the air
trunk, as the said air trunk may be made more in the form of a circle, the opposite
portions or arcs of the circular trunk being located on the same horizontal plane
The three forms are simply illustrative of various forms in which the invention may
be embodied in any other desired form and located also in any other desired
position, the position of the separating devices and discharge outlets being
correspondingly located.
A hopper or any suitable feeding device is provided whereby the stock of
grain, seed, flour, middlings or other commodity is fed into an air trunk.

page_text: In one form, the air trunk beneath the hopper, is formed with a vertical leg
provided with a discharge duct, provided at its outer end with a valve. At one
side of the duct the leg is inclined. This construction will secure a dead air
- chamber at the lower end of the leg, that is, a space where the air is little, if at all,
effected by the circulation secured in the body of the air trunk. A. separation of
the heavier stock will therefore be made at the base of the leg and be discharged
through the duct.
It will be perceived that in this form of the device the current proceeds from
the fan through the lower leg of the air trunk, and is led back into the fan through
the upper leg. The air thus rises underneath the stock as it is fed into the air
trunk, and carries the lighter portions of the stock therewith into the upper leg of
the air trunk or toward the fan.
In this form suitable separating devices may be placed in the upper leg of the
air trunk.
These separating devices consist of a cant board leading downward preferably at
an angle to a discharge duct provided with a valve or valves. From the duct rises
another cant board. Between the cant boards depends a diaphragm which may be
supported in any desired manner, as from the inner surface of the duct. This
diaphragm may be made in any suitable or desired manner or of any suitable or
desired material, as of cloth, flannel, silk, wire, wood etcetera. It is preferred that
the diaphragm should be made of porous or fibrous or analogous material, so as to
let a portion of the air current in the air trunks pass therethrough. The invention
is not however, limited to making the diaphragm of fibrous or porous material, as
the diaphragm might be made solid without departing from the invention. Where
cloth, or analogous material, is used it may be stretched upon a suitable frame.
Where the diaphragm is so made as to permit a portion of the air current to pass
therethrough, it will be evident that the force of the air current will be diminished
underneath the diaphragm, permitting an additional separation of the stock to be
made therebeneath, the heavier stock dropping by its gravity upon the cant board,
by which it is led down into the corresponding duct. One cant board rises from
the discharge duct to the base of the wall. Projecting downward at an angle in
the direction of the diaphragm is an additional diaphragm, made in any desired
manner, as above explained in describing the construction of the other diaphragm,
but preferably allowing a portion of the air current to pass therethrough, and
thereby diminishing the force of the air current passed upward between the
diaphragms. This construction and arrangement of the additional cant board and
the diaphragm, in connection with the cant board and diaphragm, facilitate the
separation of the stock at this point, in the space between the said two cant
boards, under said diaphragm. Toward the base of said cant boards will be
formed a dead air chamber. As many series of these cant boards with their inter-
vening diaphragms, dead air chamber, and discharge outlet and controlling valve,
may be provided as may be required to effect the desired number of separations, or
the separations can be effected by removing one or more diaphragms, or one or
more discharge valves, or both.
Thus following the cant boards, wall and diaphragms, dead air chamber,
discharge outlet and controlling valve, in the direction of the air current, a corre-
sponding set of cant boards is located, leading at their base to a discharge duct
provided with the controlling valve. Thereabove are also located diaphragms, and
an additional wall rises from the upper end of the cant board.
Beneath the diaphragms at the base of the cant boards is formed another dead
air chamber. It will be observed that another separation will thus be effected
between the cant boards, the heavier portions of the stock falling thereupon and
being discharged through the duct.
Following the direction of the air current, a third set of cant boards may be
provided, leading to a discharge duct at their base, controlled by a valve.
Above the cant boards are located diaphragms. At the top of one cant board
rises a wall. At the base of the cant boards is formed another dead air chamber.

page_text: There is thus effected another separation between the cant boards, discharging
through the duct.
Still another separation is provided, following in the direction of the air
currrent by the provision of additional cant boards leading to a discharge duct
having a controlling valve. Above said cant boards are located diaphragms, a
wall rising from the cant board, which, being located adjacent to the fan case, is
extended up thereto.
There is here formed an additional dead air chamber, into which an additional
separation of the stock is deposited, the stock separated at this point being
discharged through the duct. At the sides of the fan case, air boxes may be
provided, communicating with the interior of the fan case and with the interior of
the air trunk. From the top of the cant board, leads downward a wall to direct the
air current over the upper end of said cant board.
Provision is thus made for five different separations of the stock, namely, into the
dead air chambers. The invention is not, however, limited to any definite number
of separations to be thus made, in the air trunk, inasmuch as the machine may be
provided with fewer means for effecting the desired number of separations, if
preferred. Or the means for effecting the separations of the stock may be increased
by the addition of a larger number thereof, if required.
The invention contemplates, as coming within its scope, the provision of one or
more means of effecting the separations of the stock, by gravity in combination
with a continuous air current, as may be desired.
In a modification, the direction of the current is reversed, and the separating
devices are located in the lower leg of the air trunk, instead of in the upper leg.
In the lower leg of the air trunk, provision is made for four separations, by corre-
sponding diaphragms, cant boards, dead air chambers, and discharge ducts. The
air trunk is extended also to allow the air current to get back of the descending
stock and force its lighter portions forward toward the fan. Here the base of the
feeding hopper leads through the upper leg of the air trunk, the said leg being
expanded about the base of the hopper to allow the air current to pass about the
base of the hopper.
In another modification, from the fan case the current passes, coming in behind
the stock as it falls from the hopper and carrying it forward toward the separating.
devices, provision being made for five separations, which are discharged through
ducts provided with controlling valves.
The controlling valves may be of any desired construction. They may consist
of flap valves, forced open by the proper weight of stock in the corresponding
discharge duct, the valves being closed by the air pressure, or weighted to be self-
closing when the weight of the stock in the duct is not sufficient to force them
open. In this manner, little, if any, air is admitted to the air trunk, the air therein
being repeatedly cleaned and forced round and round continuously, no fresh air
supply. being required, as no air is emitted from the machine. For this reason,
there is no dust emitted therefrom, except as collected and discharged through the
proper discharge duct or ducts.
It is preferred that the diaphragms should be made adjustable. To this end
they may be hinged at one side. Any suitable means may be provided for their
adjustment.
The case of the air trunk, adjacent to the separating devices, it is preferred to
provide with glass, through which the operation going on within may be observed,
so as to effect more readily the required adjustments of the apparatus.
The air trunk may be of any suitable dimensions or form, and it should be
understood that the invention contemplates any suitable air passage or air chamber
as included in the the term "air trunk or tube," arranged and provided with
separating devices, and means for effecting an air current therein.
One of the legs or portions of the air trunk may be contracted, if desired, the
same being known as the receiving leg or portion of the air trunk or tube.

page_text: It is obvious that the stock is discharged from the discharge ducts by its own
gravity or weight.
It is preferred to provide an automatically operative valve to control and
regulate the feed of the stock into the air trunk.
By locating a suitable valve in the leg or portion of the air trunk in which the
air current is advancing to the entering stock, an air compression may readily be
formed in said air trunk to increase the force of the air current as it strikes the
entering stock.
It must be understood that the air trunk may be arranged in any desired manner,
or be of any desired shape.
The fan may be variously located, and also the separating devices, and
corresponding discharge outlets.
Dated this 1st day of December 1893.
WM. P. THOMPSON & Co.,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in or relating to Purifiers, Separators, and Graders.
A communication by DAVID J. DAVIDSON, STEPHEN G. MARTIN, and
ABRAHAM S. MARTIN, all of Port Huron, in the County of St. Clair and
State of Michigan, United States of America.
I,WILLIAM PHILLIPS THOMPSON, F.C.S., M.1.M.E., of The Agency for Foreign
Patent Solicitors, 6 Lord Street, Liverpool and 6, Bank Street, Manchester, both
in the County of Lancaster and 323 High Holborn, in the County of Middlesex,
Civil Engineer, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement.:—
The present invention has for its objects certain improvements in purifiers,
separators and graders adapted for purifying, separating and grading various kinds
of grain, seeds, middlings, flour and analogous substances which require to be
purified, separated and graded, and it aims at providing a machine for these
purposes of superior efficiency, economy and utility, one which shall dispense with
the complex mechanism, gearings and many other features heretofore common in
this class of machines, one which may be run with the least possible power, and
which shall take care of its own dust, and of the various other separations which
may be made thereby, each separation being deposited and discharged by itself. -
The invention consists of the construction, combination and arrangement of
devices and appliances hereinafter specified and claimed and illustrated in the
accompanying drawings, in which,
Figure 1 is a front elevation of a device embodying the invention, showing
the front portion of the case partially removed disclosing the interior construction.
Figure 2 is a similar view illustrating a modification, and
Figure 3 is a view in perspective also illustrating a modification of the invention
showing a portion of the case broken away, to disclose the construction of the
interior.
The invention contemplates effecting the desired purification, separation and
grading of grain, seeds, middlings, flour and other substances by gravity in
combination with a continuous air current.
More particularly the invention relates to a horizontal purifier, grader and
separator, although the invention is not limited thereto, as the invention contemplates
the hereindescribed and illustrated mechanism in whatever position it may be
placed, and in whatever form it may be made.
In carrying out the invention, a continuous air trunk or tube is provided, also

page_text: separating devices and means to effect a continuous air circulation in said air tube
or trunk, the stock being fed into said trunk, the device being provided with suitable
discharge outlets and means of controlling the same.
Accordingly A represents an air trunk which may be elongated horizontally, as
shown in Figures 1 and 2, the trunk being provided with an upper leg or portion A'
and a lower leg or portion A2, the one leading into the other at one side of the
machine, and both legs communicating with the interior of the fan case B provided
with a suitable fan B to effect a continuous circulation of air within said trunk.
The two legs A and A2 form one continuous air trunk or tube A leading from
the fan rase back thereto.
The invention is not limited solely to the form or shape or position of the air
trunk, shown in Figures 1 and 2, as the said air trunk may be made more in the
form of a circle, as shown in Figure 3, the opposite portions or arcs of the circular
trunk A being located on the same horizontal plane. The three forms shown are
simply illustrative of various forms in which the invention may be embodied in any
other desired form and located also in any other desired position, the position of
the separating devices and discharge outlets being correspondingly located.
C denotes a hopper or any suitable feeding device, whereby the stock of grain,
seed, four, middlings or other commodity is fed into the air trunk A.
In the form shown in Figure 1, the air trunk beneath the hopper is formed with
a vertical leg A³ provided with a discharge duct at a provided at its outer end with a
valve a'. At one side of the duct a the leg A is inclined as shown at A*. This
construction will secure a dead air chamber a² at the lower end of the leg A³, that
is, a space where the air is little, if at all, affected by the circulation secured in the
body of the air trunk, as below the dotted line of Figure 1. A separation of
the heavier stock will therefore be made at the base of the leg A³ and be discharged
through the duct a.
It will be perceived that in the form of the device illustrated in Figure 1, the air
current is in the direction of the arrows, the current proceeding from the fan
through the lower leg A² of the air trunk, and is led back into the fan through the
upper leg A The air thus rises underneath the stock as it is fed into the air trunk
and carries the lighter portions of the stock therewith into the upper leg A' of the
air trunk or toward the fan.
In the form shown in Figure 1, suitable separating devices may be placed in the
upper leg A' of the air trunk.
As shown, these separating devices consist of a cant board-D leading downward
preferably at an angle to a discharge duct E provided with a valve or valves, as the
valve e.
From the duct E rises a cant board D'. Between the cant boards D D'
depends a diaphragm F which may be supported in any desired manner, as from the
inner surface of the duct A. This diaphragm may be made in any suitable
or desired manner or of any suitable or desired material, as of cloth, flannel, silk,
wire, wood, etcetera. It is preferred that the diaphragm should be made of porous
or fibrous or analogous material, so as to let a portion of the air current in the air
trunks pass therethrough. This invention is not, however, limited to making the
diaphragm of fibrous or porous material, as the diaphragm might be made solid
without departing from the invention. Where cloth, or analogous material is used,
it may be stretched upon a suitable frame f, as shown more particularly in the
diaphragms illustrated in Figure 3. Where the diaphragm is so made as to permit
a portion of the air current to pass therethrough, it will be evident that the force of
the air current will be diminished underneath the diaphragm, permitting an
additional separation of the stock to be made therebeneath, the heavier stock
dropping by its gravity upon the cant board D, by which it is led down into the
corresponding duct E. The cant board D' rises from the discharge duct E to the
base of the wall G. Projecting downward at an angle in the direction of
the diaphragm F is an additional diaphragm F', made in any desired manner, as
above explained in describing the construction of the diaphragm F, but preferably
allowing a portion of the air current to pass therethrough, and thereby diminishing

page_text: the force of the air current passed upward between the diaphragms F and F.
This construction and arrangement of the additional cant board D₁, and the
diaphragm F, in connection with the cant board Daud diaphragm F, facilitate the
separation of the stock at this point in the space between the said two cant boards,
under said diaphragm. Toward the base of said cant boards will be formed a dead
air chamber d.
As many series of these cant boards with their intervening diaphragms, dead air
chamber, and discharge outlet and controlling valve, may be provided as may be
required to effect the desired number of separations, or the separations can be
effected by removing one or more diaphragms, or one or more discharge valves,
or both.
Thus following the cant boards D D', wall G and diaphragms F F¹, dead air
chamber d, discharge outlet E and controlling valve e in the direction of the air
current, a corresponding set of cant boards D² and D³ are located leading at their
base to a discharge duct El provided with the controlling valve e. 'Thereabove
are also located diaphragms F2 and F3, and an additional wall G' rises from the upper
end of the cant board D³.
Beneath the diaphragms F2 F3 at the base of the cant boards D2 D3 is formed
another dead air chamber d', as below the dotted line thereabove. It will be
observed that another separation will thus be effected between the cant boards D'
and D³, the heavier portions of the stock falling thereupon and being discharged
through the duct F
Following the direction of the air current a third set of cant boards D and D'
is shown in Figure 1 leading to a discharge duct E at their base, controlled by a
valve e².
Above the cant boards D and Ds are
top of the cant board D' rises a wall G².
is formed another dead air chamber
There is thus effected another separation
discharging through the duct E*.
located diaphragms F4 and F. At the
At the base of the cant boards D and D³
as below the dotted line thereabove.
between the cant boards D and D³
Still another separation is provided, as shown in Figure 1, following in the
direction of the air current by the provision of additional cant boards D and D7
leading to a discharge duct E³ having a controlling valve e. Above said. cant
boards are located diaphragms F and F', a wall G³ rising from the cant
board F7, which, being located adjacent to the fan case, is extended up thereto.
There is here formed an additional dead air chamber into which an additional
separation of the stock is deposited, the stock separated at this point being
discharged through the duct 3. At the sides of the fan case, air boxes B2 may be
provided communicating with the interior of the fan case, and with the interior of
the air trunk A. From the top of the cant board D leads downward a wall G to
direct the air current over the upper end of said cant board.
Provision is thus made, as shown in Figure 1, for five different separations of the
stock, namely, into the dead air chambers a³, d, d¹, d³, and d³. The invention is
not however limited to any definite number of separations to be thus made in the
air trunk, inasmuch as the machine may be provided with fewer means for effecting
the desired number of separations if preferred. Or the means for effecting the
separations of the stock may be increased by the addition of a larger number
thereof, than those herewith shown, if required.
The invention contemplates, as coming within its scope, the provision of one or
more means of effecting the separations of the stock by gravity in combination with
a continuous air current, as may be desired.
The modification, shown in Figure 2, is essentially the same as that shown in
Figure 1. In Figure 2, however, the direction of the current is reversed, as
indicated by the arrows, and the separating devices are located in the lower leg A³
of the air trunk A instead of in the upper leg A¹, as shown in Figure 1. In the
lower leg of the air trunk of Figure 2, provision is made for four separations, by
corresponding diaphragmns, cant boards, dead air chambers and discharge ducts.

page_text: In this figure the leg A³ of Figure 1 is omitted, the cant boards D and D' in this
figure being located beneath the feeding hopper. The air trunk is extended also
to allow the air current to get back of the descending stock and force its lighter
portions forward toward the fan. Here the base of the feeding hopper is shown
leading through the upper leg of the air trunk, the said leg being expanded
about the base of hopper, as indicated by the shaded lines at Q, to allow the
air current to pass about the base of the hopper, as represented by the
arrows.
So also the modification illustrated in Figure 3 is essentially the same as that
shown in Figures 1 and 2. From the fan case the current passes as indicated by
the arrows coming in behind the stock as it falls from the hopper and carrying it
forward toward the separating devices, provision being made, as shown in Figure 3,
for five separations which are discharged through ducts E E E E³ and E
provided with controlling valves el e²e and e, the duct E being shown broken
away. In this figure are shown cant boards D D D D D D D D and DB with
corresponding diaphragms F F F F³ F F F F with corresponding dead air
chambers at the base of the cant boards.
The discharge ducts may be provided, in addition to those shown, each with an
inner controlling valve, indicated by dotted lines at in Figure 3. These
controlling valves may be of any desired construction. As shown they may consist
of flap valves forced open by the proper weight of stock in the corresponding
discharge duct, the valves being closed by the air pressure or weighted to be self
closing when the weight of the stock in the duct is not sufficient to force them
open. In this manner, little, if any, air is admitted to the air trunk A, the air
therein being repeatedly cleaned and forced round and round continuously, no fresh
air supply being required as no air is emitted from the machine. For this reason
there is no dust emitted therefrom, except as collected and discharged through the
proper discharge duct or ducts. It is preferred that the diaphragms should be
made adjustable. To this end they may be hinged at one side as shown at f
Any suitable means may be provided for their adjustment, as for example rods f
The case of the air trunk, adjacent to the separating devices it is preferred to
provide with glass, as indicated at H, through which the operation going on within
may be observed, so as to effect more readily the required adjustments of the
apparatus.
The air trunk may be of any suitable dimensions or form and it should be under
stood that the invention contemplates any suitable air passage or air chamber as
included in the term "air trunk or tube" arranged and provided with separating
devices and means for effecting an air current therein.
One of the legs or portions of the air trunk may be contracted if desired, the
same being known as the receiving leg or portion of the air trunk or tube..
It is obvious that the stock is discharged from the discharge ducts by its own
gravity or weight.
It is preferred to provide an automatically operative valve K to control and
regulate the feed of the stock into the air trunk. By locating a suitable valve L
in the leg or portion of the air trunk in which the air current is advancing to the
entering stock, an air compression may readily be formed in said air trunk to
increase the force of the air current as it strikes the entering stock.
It must be understood that the air trunk may be arranged in any desired manner,
or be of any desired shape.
The fan may be variously located and also the separating devices and corre-
sponding discharge outlets.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me by
my foreign correspondents, I declare that what I claim is-
1. A. purifier, separator and grader, arranged and provided with means to effect
an air current therein, whereby desired separations of the stock supplied thereto

page_text: may be effected by gravity in combination with said air current, substantially as
set forth.
2. A purifier, separator and grader, provided with separating devices to effect
desired separations of the stock and means of producing an air current therein,
substantially as set forth.
3. In a purifier, separator and grader, an air trunk and means to effect an air
current within said trunk, substantially as set forth.
4. In a purifier, separator and grader, an air trunk provided with separating
devices and means to produce a current of air in said air trunk whereby the desired
separations of the stock may be effected by gravity in combination with the air
current, substantially as set forth.
5. In a purifier, separator and grader, an air trunk into which the stock is fed,
separating devices located in said air trunk and a fan to produce an air current
in said air trunk, whereby the desired separations of the stock may be effected
by gravity in combination with said air current, substantially as set forth.
6. In a
purifier, separator and grader, an air trunk provided with multiple
separating devices to effect multiple separations of the stock and means to produce
an air current within said trunk whereby the desired separations of the stock
may be effected by gravity in combination with said air current, substantially as
set forth.
7. A horizontal purifier, separator and grader having in combination therewith
means to effect a continuous air current therein, the purifier, separator and grader
constructed and arranged to effect desired separations of the stock supplied
thereto by gravity in combination with said air current, substantially as set forth.
8. A purifier, separator and grader having in combination a fan provided with a
fan case, a horizontal air trunk leading from said fan case back thereto, and
separating devices located within said air trunk substantially as set forth.
9. A purifier, separator and grader provided with an air trunk to receive the
stock and means of effecting desired separations of the stock within said air trunk
and independently discharging said separations, substantially as set forth.
10. A purifier, separator and grader provided with an air trunk into which the
stock is fed, formed of horizontal communicating legs, separating devices located
in one of said legs, and means to provide an air current in said air trunk, substan-.
tially as set forth.
11. A horizontal purifier, separator and grader, constructed with an air trunk
into which the stock is fed, means of producing an air current in said trunk,
and separating devices arranged to diminish the force of the air current to effect
the desired separations of the stock, substantially as set forth.
12. In a purifier, separator and grader, an air trunk and means to produce an
air current therein, the construction and arrangement being such that the air current
will strike the entering stock supplied thereto opposite the direction of the air
current, whereby the heavier stock will be separated by gravity and the lighter
portions of the stock will be carried forward, substantially as set forth.
13. In a purifier, separator and grader, means of producing an air current
therein, and separating devices to effect a gravity separation of the stock in com-
bination with said air current, substantially as set forth.
14. In a purifier, separator and grader, means of producing an air current
therein, separating devices to effect gravity separations of the stock in combination
with the air current and discharge outlets for each of said separators, substan-
-tially as set forth.
15. In a purifier, separator and grader, an air trunk or chamber and means for
effecting an air current therein, said air trunk or chamber provided with one or
more dead air chambers, substantially as set forth.
16. In a purifier, separator and grader, a fan, an air passage through which a
current of air is directed from the fan back thereto, a cant board located within
said air passage, a diaphragm located above said cant board and a discharge outlet
located at the lower end of the cant boards, substantially as set forth.

page_text: 17. In a purifier, separator and grader, an air passage, means of effecting an air
current therein, a cant board, a diaphragm and a discharge outlet at the base of
the cant board, said cant board and diaphragm the one adjustable in relation to the
other substantially as set forth.
18. In a purifier, separator and grader, an air passage, means of effecting an air
current therein, a series of cant boards, diaphragms suspended above the cant
boards and discharge outlets at the lower ends of the cant boards, substantially as
set forth.
Dated this 31st day of August 1804
WM. P. THOMPSON & Co.,
Agents.