E3

Fig 2.

J2

B

M

K

W

W

Fig. 1, is a vertical section in a line at right angles to the smoke and draught flue.

Fig. 2, is a similar section directly through the smoke and draft flue.

top edge of the pipes F, F, protrudes above the flanges to a slight degree, as indicated at g, g.

The fire-pot flares at top and contracts at its bottom, the flare and contraction being gradual The section of the metal, of which the pot is made, shows a gradual decrease in thickness from the center of the depth of the pot in an upward and downward direction as indicated at 1, 2, 3. This construction or form of the metal insures an equable heating of the pot at all parts, and a uniform expansion and contraction by the principle of conduction, the thickest and most intensely heated portion, imparting to the thinnest or less intensely heated portions, a large amount of its heat, on the principle just mentioned.

Above the fire-pot and vertical pipes the coal supply reservoir G, is arranged. This reservoir is constructed with a flange, h, at its base, said flange turning down at its outer edge so as to form a right angle, or thereabouts, as shown at i. The rim i of the flange fits down upon the rim of the fire-pot, and incloses the top opening of the fire-pot of the vertical pipes with a continuous chamber j, as represented; the said chamber constituting an enlargement to the upper portion of the fire-pot as it were, and thus giving increased room for the expansion of the flame.

*

The diameter of the coal reservoir is decreased below the point where the body of supply coal is suspended by means of an extension or ring flange K, which is in form of an invented frustum of a cone. This flange also serves in connection with a detachable ring, v, which also is in form of an inverted frustum of a cone, to form a frame or sash for the reception of firebrick, or other fire-proof material, as shown at m. The ring, v, has a horizontal flange and bolts by the same to the under side of the flange n, of the coal supply reservoir. The fire-brick are shaped so as to form, when put together, an inverted frustum of a cone, and they, therefore, when clamped with the devices k, v, cannot de359*] *"A is a base of our stove, constructed scend separately out of their places, nor can with a chamber B, which extends around and they do so unitedly, as the largest circumferbeneath the top-plate of the said base. In this ence of the conic frustum m, cannot pass chamber, air may be admitted through the front through the space between the lower passage a. Upon the top plate of the base A is ends of the devices k, v. It will be ob- [*361 erected a support C for horizontal grate D, and served that the fire-brick continues the contrac a fire-pot E, as shown. The support forms a tion of the coal supply reservoir, and thus inchamber below the grate, and out of the front of sures a gradual descent of the supply coal upon the support a portion of metal is removed at b, the central part of the bed of incandescent coal, so that air to the fire on the grate may have and at the same time leaves a large and open free access when the ordinary regulator or space outside of the conic frustum m, for the damper is open. In order to insure the passage free burning and expending of the gases or of the air to the fire only from below the grate, flame. This result is also furthered by the disha cut-off c extends out from the upper front ing form of the flange, h, the same forming a part of the support C, and rests upon the two large circulating flame channel, j, all around lateral stops d, which extend out from the front the upper edge of the fire-pot, as illustrated. of the support, as shown. The top plate of the The reservoir G, is continued up to a horibase at points outside of the support C, is per-zontal division-plate I of the stove, by means of forated with three apertures, F, F, F, which an extension Gas shown. The division-plate I 360*] communicate with the chamber B. The has a large coal induction hole in its center, and apertures F, F, have vertical pipes, F, F, several hot air passages o, o, near its circumferplaced in or around them, while the aperture Fence or outside of the circle of the coal supply has the draught and smoke pipe or Flue Freservoir, as shown. Around the center hole n, placed in or around it as shown. The pipes F, F, extend to the upper rim of the fire-pot E, and connect to perforated flanges or ears of said pot; so that a space f, exists between the pipes and fire-pot as shown. The outer portion of the

there is constructed a small combined cylindric and conic hopper J, which is furnished with an adjustable valve s, and a removable cover-plate J, as hereinafter described. Through and from the rear of this hopper there extends a branch

DA

fd

R

Fig 4

J

B

"Fig. 1 is a vertical longitudinal section of a stove patented by us at previous dates, with our improvements of the present date applied to it. Fig. 4 is a vertical transverse section of the

of segment or angular form in their cross section, and of fire-proof material fitted between the rings, all in such manner that the throat of the reservoir is supported on the interior of the stove and forms a continuation of the fire-pot, and still not be a fixture, so far as bolts or other fastenings, which will not yield to expansion and contraction, are concerned, with either the stove or fuel reservoir.

It consists: 4, in a poke hole in the fire pot which has an angular branch hole leading down into the ash-pan pit, whereby the live coals which are liable to fly out upon the floor when the poker is moved back and forth, are conducted down into the ash pit.

It consists: 5, in the adaptation of a portable grate with inclined top, a box frame and legs and a handle, for use in combination with base burning, reservoir stoves, whereby the starting of the fire in such stoves, although the supply reservoir may be changed, is rendered a very convenient and ready matter.

It consists: 6, in providing the ash-pan with apertures in its circumference, at opposite points so that the poker may be inserted through these holes, and the pan carried out with hot ashes in it without liability of burning the hand.

As the main features of our present stove are shown in the letters patent granted to us on the date heretofore mentioned, we do not deem it necessary to describe here anything more than those parts which we regard as essential changes and improvements on the stove described in said patent.

Our first improvement is carried into practice by casting the fire-pot A with a rectangular, eliptical or circular extension, a, at one or more points of its upper edge. This enlargement we extend through an opening in the outer casting or jacket, B, of the stove, and close it with mica or other transparent material, C, as shown. We may find it more practical to form a short ledge on the upper edge of the fire-pot, as at b, and cast the enlargement c on the part D, which forms the expansion flame passage E, as shown. In any case the illumination window must be constructed so as to confine the flame and gases at this point within the flame chamber E. Our second improvement is carried into practice by casting in like manner an enlargement of proper The nature of this invention, which is an im- form to make a branch flue F, on the upper edge provement on our stove patented May 7, 1861, of the fire-pot, or on the lower edge of the [*365 and re-issued February 3, 1863, consists: 1, in part D, as represented. This branch flue we the construction of an illumination window or run into the smoke-pipe or draught flue G, and windows at one or more points in the continuous in order to open and close it at will, we have arflame expansion chamber or channel which is ranged within it a damper or valve I, which has about the base of the coal supply reservoir and its rod, by which it is turned, extended to the the top of the coal burning fire-pot, in combina-outside of the casing of the stove. By opening tion with a descending flue which leads to a chamber about the base of the stove and from such chamber into a chimney flue.

.whole stove.

It consists: 2, in the construction of a damper draft flue in the continuous flame expansion chamber or channel, located, as just stated, in combination with a descending flue which first leads down into a chamber about the base of the stove, and then into the chimney flue, with which the damper draught flue connects directly at the top of the fire-pot.

It consists: 3, in the construction of the throat of the fuel supply chamber, of two rings

244

the damper, a direct draught is obtained, and the fire can be kindled very speedily, and the draught does not have to pass up through the body of coal in the reservoir, as in our other patented stove. When the damper is closed the highly ignited gases pass down the descending flues JJ, as in our former patent. We will here state that we have slightly modified the base of our stove by increasing the depth of the ash-pit K, and dispensing with a chamber or space underneath the ash pit. This space or chamber, L, in which the heated products of combustion circulate to heat the base of the stove, and

87 U. S.

to the draughts or smoke flue, being only around | improvement in base-burning reservoir stoves the ash-pit.

Our third improvement we carry into practice by casting two rings of circular form, and of segment or angular form in their cross section, as indicated at d, d. Between these rings we insert fire-brick sections which are segments of a hollow frustum of a cone, and in their transverse section are in form adapted to the form of the rings, as shown. These rings and bricks are firmly riveted together, and the conic throat thus formed is supported free, as to expansion and contraction, on a ledge f, formed on the part D, as represented. When the throat is placed on the ring, we insert within the coal supply reservoir, just above it, an inverted frustum of a hollow cone, as shown at g, so as to ease the descent of the coal and prevent a lodgment in the corner formed by the portable throat and the reservoir. We do not confine ourselves to forms of throat, as our invention consists in a portable throat constructed of two rings and fire-proof material, so that it may be suspended free as to bolt fastenings, and have every chance to expand and contract independent of the stove castings.

is:

1. The combination of the illumination openings, flame expansion chamber, coal supply reservoir, fire-pot, descending flue, and draught flue, substantially in the manner and for the purpose described.

2. The combination with the flame expansion chamber, formed at the base of the coal supply reservoir, and around the upper edge of the firepot of a base-burning stove, of the branch draft flue, with damper, when the same are located with respect to the flame expansion fire-pot, coal supply reservoir, and descending combustion flues, substantially as and for the purpose described."

There were three other claims not alleged to be infringed.

The following is a summary description of the stoves with the improvements patented by the complainants in the patents alleged to be infringed, taken from the statement of the appellee's counsel:

The stove described and represented in the patent, "B," consists of a fire-pot, larger at the upper end than at the lower end; a grate at the Our fourth improvement is carried into prac-bottom, with an ash-pan below, to catch the ashes tice by forming a branch or vertical extension that drop through the grate, and open to admit M, of tubular form on the under side of the or- the draught which passes up through the grate dinary poker-hole N, and have the said extension and charge of coal. Above the fire-pot there is a communicate with the poker-hole N, and there- feeder of cylindrical form, provided with a cover from lead down through an extension of the base at the upper end, through which the charge of of the fire-pot or grate into the ash-pit, as rep- coal is introduced, and it is contracted at the resented, so that if a red-hot coal should be lower end, which is about on a level with the drawn out by the poker, it will in its passage upper edge of the fire-pot. The space all around fall down through the branch M into the ash- the upper edge of the fire-pot is inclosed, to pit. form what is termed the flame expansion chamber, which chamber extends up and is connected with the outside of the lower part of the feeder;. and from this chamber there are two descending flue tubes, one on each side, which extend down and connect with a horizontal flue chamber in the base of the stove; and from this horizontal chamber there is a vertical flue pipe at the back, leading to the chimney, so that the products of combustion in this, as in all revertible flue stoves, rise from the surface of the ignited coal in the fire-pot and over the upper edge thereof, pass into the flame expansion chamber, down the two revertible flue tubes, to the flue chamber below, and then up the vertical flue pipe to the chimney. The cover of the feeder is double, and from the space between them there is a horizontal pipe leading to the vertical flue or exit pipe, which leads to the chimney, so that when the inner cover of the feeder (marked A, on the drawing) is open, the draught from the fire-pot will be directly through the charge of coal in the feeder to the space (F) between the two covers, and through a short horizontal pipe (G) to the vertical pipe (E) that leads to the chimney. In this way the stove is changed from a revertible to a direct flue stove, just as all revertible and direct draught stoves have been made, without a feeder, long prior to 1860. The entire stove is surrounded by a cylindrical casing, having apertures for the admission of air to be heated, as is common in many stoves known and used prior to 1860.

Our fifth improvement is carried into practice by casting a hollow or box grate frame O, with its upper surface inclined. Within the center of this frame we set a grate, P. To the front of the frame we attach a handle, Q. From the edges of the frame a flange h extends, and to the under side of this flange, legs, ii, are fastened. This portable auxiliary grate is set in the place occupied by the ash-pan when it is desired to start a fire in the fire-pot; and when thus placed, the air has a free circulation under it and through the grate, as the bottom of the box frame is wholly open. The kindling is placed on the grate, and in a very short time after applying the match to it, the fire in the stove will be in condition for removing the portable grate, clasing the damper I, and replacing the ash-pan. If the kindling was simply placed on the ash-pan, the starting of the fire would not be so effectual as no draught below is obtained, and if the base plate of the stove was used, then the distance would be so great from the main grate, that the end desired would be very imperfectly and slowly attained. It is our intention to use a portable grate, which reaches pretty close to the main grate.

To carry into practice our sixth improvement we simply have to bore a hole R, in each side of the ash-pan as represented, and provide a poker of a size corresponding to these holes, and of suitable length to reach across the pan. We draw out the pan by its ordinary handle far enough to pass the poker through the hole, and lift by and carry the pan on the poker without burning our hands.

What we claim as our invention and as an

In this stove there is a serious and fatal defect.

The object of a self-feeder or reservoir is, to supply coal to the fire-pot, but not to burn the

coal within the reservoir, because it is not pro- | walls and a grate at bottom, which fire-pot rests vided with any outlet to the chimney, when the necessarily on a base. The fire-pot is surrounded direct draught is closed, and the revertible by the outer casing, which is not perforated, draught is open; but, as the direct draught is and placed at such distance as to leave an anthrough the reservoir or feeder, there is no way nular, flue space all around between it and the in which the direct draught can be used with fire-pot, which flue space communicates with a out igniting the coal in the feeder. This ob- flue space in the base of the stove, and this, in vious defect was cured afterward in patent, Ex- turn, communicates with a vertical flue pipe hibit C. leading to the chimney. From the annular space above the upper edge of the fire-pot there is a short lateral pipe, with a damper, leading into the vertical flue pipe, which conducts the products of combustion to the chimney. When the damper in this short lateral pipe is open, the draught is direct, and when closed the draught is revertible, that is, the products of combustion then pass over the upper edge of the fire-pot down to the annular flue space, all around between the outer casing and the fire pot to the base of the stove, and thence up the vertical flue pipe to the chimney. There is in front and immediately above the upper edge of the fire pot, illuminating openings covered with mica, through which the fire and the flame can be seen.

The stove in the patent, Exhibit C, differs from the one in patent, Exhibit B, only in the addition of mica windows to admit light into the room from the fire in the fire-pot, and in adding a flue for the direct draught, instead of causing the products of combustion to pass through the feeder or reservoir, when kindling or exciting the fire in the fire-pot.

The following is a drawing of Exhibit A, the stove manufactured by the defendants (appellees) alleged to infringe plaintiffs' patents:

AMERICAN GAS-BURNER.

So far appellee's stove was known as the "American Gas Burner" (see figure); and such stoves were extensively manufactured and sold by appellees long before the alleged invention of appellants. Such is the uncontradicted evidence, and to this kind of stove appellees simply applied a feeder or reservoir to supply coal to the fire-pot, instead of supplying the coal by shovel, hod or scuttle.

On the question of infringement, one of the principal witnesses for the plaintiff, Dennis G. Littlefield, testified as follows:

Q. Please state whether you are acquainted with the organization and construction of a base-burning stove, manufactured by defenaants, and marked "complainants' exhibit A.?”

A. I am acquainted with said stove, and un