US657662A - Controlling means for explosive-engines. - Google Patents

Description

Patentedsept. n, |900.

F. A. LA ROCHE. CONTROLLING MEANS FOB EXPLOSIVE ENGINES'.

(Application tiled Mar. 14, 1900.)

2 Shasta-Sheet l.

(No Model.)

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No. 657,662. Patented S`ept. Il, |900. F. A. lLA ROCHE.

CONTROLLING MEANS FOR EXPLOSIVE ENGINES.

(Application med mr. 14, 1900.)

(No Model.) 2 Sheets-Sheet 2.

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UNITED STATES PATENT OEEItnE0 FREDRIOK A. LA ROCHE, OF NEW YORK, N. Y.

CONTROLLING MEANS FOR EXPLOSlVE-ENGINES.

SPECIFICATION forming part of Letters Patent No. 657,662, dated September 11, 1900.

Application tiled March 14, 1900. Serial No. 8,617. (No model.)

To all whom, it may concern:

Be itknown thatl, FREDRICK A. LA ROCHE, a citizen of the United States, and a resident of New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Gas-Engines, of which the following is a specification.

My invention relates to gas-engines having multiple cylinders operated on the principle of what is generally known as the Otto cycle and using for their fuel a mixture of atmospheric air and an inflammable gas or some suitable hydrocarbon and ignited in the cylinders by an electrical igniting device; and the object of my invention is to et'l'ect a considerable reduction in the weight of such engines per horse-power of their capacity, to simplify the igniting device, and render it more efficacious and positive in its performance, while at the same time lhave arranged said ignition device by my peculiar construction so as to cause ignition of the explosive mixture in the cylinders at a time best suited to t-he demands of load necessary to give the greatest torque on the crank-shaft and to etl'ect the greatest possible acceleration of the crank-shaft under load byincreasingthe starting-torque as much per horse-power ot' the capacity of the engine as possible. It is also the object of my improvements in gasengines to provide `a ready and effective means for starting the engine automatically when at rest with a minimum of labor on the part ot' the operator and by a construction which is both simple and effective and to devise a simpler and more effective means of governing engines of this class than any of which at the present time I am aware, as Well as to provide a better, simpler, and more economical means ot' regulating the supply of fuel to the engine than that which has, to the loest of my knowledge, been in vogue previous to my invention, all of which l attain by carrying out my improvements in the manner described in this specification and fully illustrated in the drawings forming part thereof, in which the different features of my invention are illustrated in the several figures, respectively, wherein- Figure l is aside sectional elevation of my improved gas-engine, showing particularly the governor-shaft and crank-shaft and the electrical generating fiy-wheel or dynamo-armature and the system of electrical distribution for starting the engine when at rest. Fig. 2 is a front sectional view of the same looking toward the end of the crank-shaft and governor and showing the disposition of the oiling system and exhaust-cylinders. Fig. 3 is a detailed sectional View of the crankcase of my improved engine, showing the disposition of the valve-stein. Fig. et is a vertical section of my improved carbureter and fuel-supply regulator, showing the manner in which the cam on the engine-shaft controls the supply of fuel to the engine. Fig. 5 is a detail plan view of my improved multiple crank-box. Fig. 6 is a sectional detailed view of the same. Fig. 7 is a sectional vertical view of a modification of the fuel-feed mechanism shown in Fig. 4.

Similar numerals ot' reference refer to similar parts throughout the diiterent views.

The type of engine which I have illustrated in the drawings and to which the different figures refer I shall designate the transportation type,being more particularly adapted to the propulsion of launches orthe like orto the propulsion of road-Vehicles, tramcars,&c. I prefer in this type of engine to employ three cylinders l, 2, and 3, situated at points radially to the crank-shafts and at angles one hundred and twenty degrees apart, as shown in Figs. 1 and 2. Each of the three cylinders is provided with a cylindrical tubular. piston 5, adapted to move freely within the cylinders, as commonly employed in gas-engine construction. Swinging within the cylinder-piston 5 on the wrist-pin 6 are the connecting-rods 7, having segmental bearing-terminals 8, which bear against the crank-pin 9. rlhe three segmental bearing-terminals S of the connecting-rod 7 are held to their seats upon the cran k-pin 9 by the collars 10. These collars are adapted to admit ot' freedom of oscillation of the segments 8 upon the crankpin 9 while the engine is in operation and are provided with bearing-surfaces having facilities for lubrication, and inasmuch as that they are adapted to merely hold the connecting-rods 7 together upon the crank-pin 9, so as to move the pistons 5 against friction and air resistance, they may be made comparatively light, as shown in the drawings.

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` puppet-valve 1G.

Surrounding the cylinders 1 and 2, which ex tend radially from the crank-case 11, are the water-,jacket cylinders 12, as customary, supplied with water in the usual manner, for taking up the excessive heat of the cylinderwalls'when the engine is in operation.

Cast With the cylinder-heads 13 are the intake-valve chambers 14, having inlets 15, adapted to be connected to the fuel-supply pipe 48, (shown in Fig.1,) receiving its supply of fuel from the carbureter 85, through the fuel-supply outlet 49, and spring-retracted It will be readily understood that upon an inward movement being given to one of the pistons 5, so as to increase the clearance-space 1'7 in the cylinder 3 sufficiently, the puppet-valve 16 will be forced in against the action of its retracting-spring by virtue of the reduction of pressure in the aforesaid clearance-space 1'7, thereby openin 0: a passage from the inlet 15 to the interior of the cylinder, thus enabling the explosive mixture to enter the cylinder.

Contiguous with the cylinder-heads 13 and intake-valves 14 are the balanced spring-retracted puppet exhaust-valves 18, lifted by the cams 19, revolving on the shaft 4, driven by the countershaft 29 through the system of gearing, to wit: driving-gear20, keyed to engine-shaft 4, reduction-gear 21, and drive reduction-gear 22, both keyed to countershaft 29,and reduction-gear 23, secured to cams 19. The gear relation is so arranged as to operate the valves in a manner suitable for the Otto cycle, and has therefore a ratio of two to one-that is, for every two revolutions for the engine-shaft 4 the counter-shaft 29 shall make one revolution, which will drive the cams 19 through the vsystem of gear, as aforesaid, at the same speed, thereby lifting the exhaust-valves 18 by the valve-stems 25 and rolling contact-points 26 once in every two revolutions of the engine-shaft 4. The disposition of these cams and the manner in which they are adapted to operate the valve 18 by their stems 25 alternately maybe more clearly understood by reference to Fig. 3, in which it will be observed that the valve-stems 25 are provided at their ends nearest the cams 19 with rollers 26, so as to reduce the friction at the point of contact with the surface of the cams 19 when the engine is in operation. The valve-stems 25 are guided by the tubular bearings 27, which are secured at their outer ends to the crank-case 1 and at the inner end by the ring 28. It will be readily understood that by rotating the crankshaft 4 a movement will be communicated to the counter-shaft 29 through the gear, as already described, lifting the valve 18 once for every two revolutions of the engineshaft 4. The exhaust-valve 18 has a port 50 leading to the closed mu'ffling exhaust-head 30, with perforated exhaust-tube 31 tightly secured to that end of the exhaust-head nearest the crank-shaft 4as clearly shown in Fig. 2. lightly secured to the bottoni of the exhausthead 30 is the annular air-shaft or hot-air' jacket 32, (with an outlet 33,) open at the top to receive the cooler air` from the surrounding atmosphere, which after being warmed by the hea-t of the exhaust, which raises the temperature of the cylinder-walls, is carried by the outlet 38 to an electrically-controlled needle fuel-controlling valve 34 and carbureter A portion of the exhaust-gases is led off by the small branch exhaust-pipe 3G, which is loosely coupled with the crank-pinlubricating feedpipe 88, whereby upon each impulse of the exhaust a portion of the oil in the supply-tank 37 is blown through the pipe 88 and onto the crank-pin 9 and sectional crank-pin box 8 during every two revolutions of the crank-shaft 4. This keeps up a continual lubrication of the crank-pin bearings. The surplus of oil thus fed to the crank-bearings drops back into the oil-tank 37 and is being continually used over and over until at length it may be removed by the faucet 39.

Axially sliding upon the engine-shaft 4 in a keyway is the fuel-supply-regulating cam 51, having a gradual rise from zero at its inner end nearest the crank-box 1 of about eight per cent. of its length at the other end. In Fig. 4I have shown an end view of the cam 5l and the manner in which it is adapted to operate the fuel-supply valve. Secured to the carbureter 35 is an arm. 52, to the Vfree end of which is pivoted a lever of the viirst order, one extremity of which is caused to bear against the surface of cam 51 by the retractiug action of the tension-spring 54, secured tothe opposite end of lever 53, the other end of the retracting-spring 5-1- being connected to the free end of the needle-valve stem 55, the other end of this being fitted to the fuel-supply valve 84. rPhe valve-stein 55, carrying the armature 57, passes through the inner core of the annular electromagnet 5G, a coni pression-spring 58 being' adapted to keep the stem 55 in toward the valve 34, so as to shut off the flow of oil or gasolene entering the carbureter 85 when the engine is inoperative, is overpowered by the stiffer tension-spring 54, when the lever is thrust in toward the carbureter 35 by the rotation of the cam 51 when the engine is running, there by admitting that quantity of fuel into the carbureter through the inner end of the pipe which is admitted by way of the hand feed-valve 59 through the inlet GO. \Vhen a greater quantity of gasolene shall have been admitted to the carbureter by the action of the valve 34 than that which can be retained in the gaseous state in the quantity of air contained in the carbureter, a quantity of the liquid would have been precipitated, with the result that the fuel would have been carried to the engine in a liquid stale rather than in the form of a combustible gas properly mixed with the air for the rapid combustion which impulse-engines demand. To obviate this difficulty, l have devised the elec tromagnetic check for the valve 2:54, compris- TIO ing the circuit-closing float 6l, carrying the contact-making stem 63, adapted to move freely up and down in the pocket 62, and the insulated contact-spring 64 and battery 65, connecting electrically one end of the electromagnet 56 and contact-spring 64 by suitable electrical conductors and connections, the other end of the electromagnet-windings being connected to the framework. Vith this manner of checking the overflow of gasolene it will be readily seen that only a very small quantity of liquid in the pocket 62 would be necessary to lift the oat 6l, causing the stem 63 to make contact with the insulated contact-spring 64, thus closing the circuit through the metallic framework, electromagnet, conducting-wires, and battery 65, thereby energizing the electromagnet 56 suficiently to hold the valve 34 closed by the stem 55 and armature 57, thus shutting off any further supply of gasolene to the carbureter. After a quantity of air shall have been passed through the carbureter 35, the heated air being admitted by the air-supply pipe 33, as previously stated, the gasolenesupply being shut off, the saturated inflammable air being drawn out at 49 by the enginecylinders will become weaker in gasolene, whereupon its absorbing property will have been increased, and after having absorbed a snfiicient quantity of that left in the drippocket 62 the float 6l will fall, which will canse the stem 63 to break contact with the electrical conductors and spring and the aforesaid electric current through the magnet will be interrupted, thereby releasing the needle-valve 34 and allowing the engine to again automatically supply oil to the carbureter, as before.

In the arrangement which I have just shown and described and as illustrated in Fig. 4 I have devised a means of transmitting power to the valve-stem 56 through the medium of a tension-spring, which may be made to operate more or less sensitively', depending to a greater or less extent upon the conditions under which it shall be used. When I employ the carbureter for aerating the fuelsnpply of gas-engines adapted to propel vehicles or the like, where there is a more or less possibility of vibration and jar, I prefer to transmit power to the valve-stem through the rigid connection shown in the modification, Fig. 7, ot' my improved electrically-controlled fuel-supply valve. In the modification the armature 57 of the electromagnet carries a latch 66, which when the electromagnet is not energized engages the upper end of the lever 53, and upon the magnet being energized, as already explained, the latch 66 is lifted by the armature clear of the end of the lever 53, thereby rendering the valve-stem inoperative, as already described for the construction shown in Fig. 4, and in each case the electromagnet. is arranged so as to cut off the snpply of gasolene when the electrical circuit is closed by the circuit-closing devices.

The arrangement of the cam 51 (shown in Fig. l) admits of variations in the supply of gasolene by changes in stroke ot' the valvesteln. 55 as the cam rotates, bearing against the lever 53 at different points along the line of its rise. When the greatest amount of stroke of the valve-stein is required, the cam 5l is drawn back into the position shown in Fig. l by the lever 67,whieh engages a groove and collar at the inner end ot the cam 5l, which brings that part of the cam having the greatest rise into bearing with the lever 53 as the engine-shaft rotates; but by moving the lever 67 inthe opposite direction the cam may be moved through all decreasingdegrees of rise while bearingagainst the lever 53 down to zero. To that end of the crank-shaft 4 opposite the cam 5l is keyedwthe ily-wheel 68 G9, the rim of which, 69, is wound as a @tamme-ring armature, which together with the field-magnets and commutators 7l and brushes 72 constitute a dynamo-electrical generator, the dynamo leads 73 are carried back to the pole-changing controller 74 and storage battery 75. When the controlling-- lever 76, comprising the parts 76 and 76, is standing in t-he position shown in Fig. l, the pole-changer is thrown so as to connect the dynamo-circuits up with the storage battery as a generator; but when the lever 76 shall have been swung upon the pivot SO in an opposite direction to that shown in the drawings the pole-changer will have been thrown into an opposite direction, changing the circuits of the generator, so as to cause it to run as a motor driven by the electrical current from the storage battery 75. The controllinglever 76 has a sheath 76, which swings upon the perforated pivot SO, the inner core of which, 76", is adapted to be rotated in the perforated pivot 80.

The controller 74 is provided with a variable resistance 78, having contactpoints 77 so arranged that when the lever 76 is throwntoward the center or vertical position more resistance shall have been thrown in as it passes over the contact-points consecutively; but when it shall have arrived at the center or vertical position, however, it shall have broken contact, and any further movement of the lever 76 in the same direction shall reverse the electrical connections of the generator by the action of the pole-changer and close the circuits through the highest resistance offered by the rheostat 78, but decreasing the resistance as lever 76 is moved farther and farther in the same direction over the contactpoints 77. Thus it will be readily understood by following the path of the current through the circuits shown in the drawings how the dynamo-current may be cut down to zero by a movement heilig given to the lever 76 before converting the dynamo into a motor and how the potential of the storage-lutttery current is kept down at the motor-terminals and grad nvally increases as the motor gets under speed,

making the reversal of conditions from dy- IOO IKO

2i strasse namo to motor without the danger of burning out the insulation on the wire of the armaturewindings attending the older devices for ef* fecting such change when two or more levers and extra resistances are required to accomplish the same end, thereby complicating the operation of the controller and increasing the liability to err. At the pivot end of the lever 76 is the two-point rotating-switch 8l, a contact-point of which, 82', is connected to ene pole of the storage battery 75, the other pole thereof being electrically connected to the insulated diagonally-disposed commuta tor-segment Set, adapted to make and break contact with the rotating` brush S3, which is carried around by the fly-governor S5. The switch-lever 87 of the switch Sl is connected to one terminal of the primary of the induction-coil 82 and the other terminal of the said primary is connected to the metallic frame work of the engine, so as to establish through the same electrical connection with the contact-making brush 83, as shown in Fig. l. Thus it will be readily understood how I am enabled by my improved controlling-lever to start the engine-shaft forward by a forward movement of the lever and increasing the speed of the rotating shaft as the lever is moved forward farther and farther in the same direction and gradually shutting down as the lever is brought back to its normal position, then'how, by the lever being reversed, the direction of the rotation of the power-shaft is reversed, with gradual increases in speed as the lever is drawn back farther and farther, and that by rotating the handle of my improved lever how I am enabled to control the propulsion of the power-shaft by the aetion of the gas-engine at any period during the backward or forward movement of my controlling-lever, or when the same is in its normal position, thereby operating both the engine and its electrical starting mechanism, so as to back up, stop, or run forward faster or slower in either direction, or stop, with a single operating-lever.

Upon the rotation of the counter-shaft 29 by the operation of the engine crank-shaft a and gears when the engine is in operation, as already described, the contact-brush 83 shall be carried around by the governor, so as to make contact with the commutator-segment Sel., thereby closing the electrical circuit through the battery and induction-coil primary, causing the secondary current to jump across the spark-gap 8S in the cylinder-head. (Shown in section in Fig. 2.) Upon a sufficiently-rapid rotation being given to the counter-shaft 29 the governor 85 and brush S3 will have moved from the position shown by the dotted lines into that shown by the solid lines in the drawings, and by virtue of the diagonal position of the segment 84: the brush S3 shall have made contact at an earlier period, when by the counter-shaft 29 revolving more rapidly the governor fly-balls are thrown out into position of the solid lines,

thereby causing the spark to pass at the spark-gap at a time earlier in the stroke of the piston in the particular cylinder for which the commutator-segment S4- is connected. By this feature of my invention it will be understood by those versed in the art to which my invention pertains that I am enabled to increase the thermodynamic elliciency of my improved gas-engine, first, by increasing materially the isothermal range of the gases after ignition, or, graphically speaking, obtaining a higher isothermal curve, and, second, approximating more exactly an adiabatic expansion of the gases in the cylinder upon a forward movement of the piston during its working stroke, thus more closely approximating the conditions of Carnots cycle as the speed increases. Therefore with the same amount of gas ignited in the cylinder upon an increase of speed the initial piston-pressure will be increased with the effect that the torque on the crank-shaft will be kept up in spite of the fact that the crank-shaft would be revolving faster. This I deem of considerable importance in the art of engine construction and will undoubtedly prove of value when used as a means of regulating the torque of engines adapted to propel vehicles, launches, or the like where an increase or constant torque of the powershaft is required with an increase of speed of the said shaft. Though I have shown a simple and efficacious means of carrying out this feature of my invention in Fig. l, I de not care to limit the scope of my invention in the manner in which I have herein illustrated and described the same, as I am aware that many minor changes may be made in the details ol construction without departing in the least from the spirit of my invention.

For the three cylinders shown in the drawings I employ three commutator-segments having such relation with the contact-brush 83 as to close their respective circuits at the proper time for ignition of the gases in cach cylinder. In order to carry out this feature of my invention, I employ three separate induction-coils having a terminal of their primaries each electrically connected with a segment in a similar manner to that which I have just described for one cylinder.

In the event of the storage battery being inoperative by becoming discharged I employ an auxiliary igniting-battery 86, having one of its poles connected to the other contact-point of the switch 8l and the other pole connected to the same circuits and connections as these to which the storage battery is connected. It will be readily understood that by rotating lever 7G in one direction and its bearing in the pivot SO the switch Sl is adapted to turn on the current of the storage battery 75, and by giving it an opposite rotation the storage-battery current shall be shutoff, and by continuing the rotation of the lever 76 the primary-battery current shall be thrown onto the igniting-circuit in lieu of the secondary IOO battery in the first instance, whereby T am enabled to change from primary 1o secondary battery for my ignitingcircuit by a change in the direction of rotation of the handle of the operating-lever 76. It will therefore be understood that with but one lever 7G I am enabled lo control two sources of electrical supply for the igniting-circuit of my improved engine as well as to control the current which drives the motor or the cnrrent of the electrical generator which charges the storage-batteries; and having fully described my invention, so that any one who is versed in the art to which it pertains can operate and use the same,

What I claim as new, and desire to secure by Letters Patent of the United States, is-

l. In a gas-engine, in which the torque of the rotating power-shaft varies according to an inverse ratio of the speed, the combination therewith, of ignition mechanism,and means controlled by the speed of the engine, whereby the ignition is automatically timed in such a manner as to automatically compensate for the loss of torque, due to increase of speed ot' said power-shaft, substantially as described.

2. In a gas-engine, in which the torque of the rotating power-shaft varies according to au inverse ratio ofthe speed, the combination therewith of ignition mechanism, and means controlled bythe speed of the engine, whereby the ignition is automatically timed in such a manner as to automatically compensate for the loss of torque due to increase of speed of said power-shaft, and a fuel-feed mechanism driven by the engine for operating the same, and a hand controlling means for said driving mechanism for controlling the torque, substantially as described.

3. In a gas-engine, in which the torque of the rotating power-shaft varies according to an inverse ratio of the speed, the combination therewith of ignition mechanism, and means controlled by the speed of the engine, whereby the ignition is automatically timed in such a manner as to automatically compensate for the loss of torque due to increase of speed of said power-shaft, and a fuel-feed mechanism driven by the engine for operating the same and a hand controlling means for said driving mechanism for controlling the torque, and means controlled by the eX- cess supply of said fuel for regulating` the fuel-feed, substantially as described.

4. In a gas-engine, the combination with the rotary power-shaft thereof, of a fuel-feed mechanism, driven by the engine for operating the same; hand controlling means for said driving mechanism, and means controlled by the excess supply of said fuel for regulating the feed thereof, whereby the torque is controlled and regulated according to the variations in speed of said shaft, substantially as described.

5. In a gas-engine, having a carbureter adapted to convert liquid fuel for said engine into a gas, the combination of thtx valve or valves, adapted to admit said fuel to the carbureter, andk means operated by said engine for carbureting the supply of fuel, which is adapted to pass through said valves, and of the supplemental controller for shutting oit the supply of said liquid, actuated by an excess supply of liquid, when said gas shall have been oversatu rated with said liquid fuel, substantially as described.

6. In a gas-engine, having an electricaligniting device, the combination of a stationary contact-making com mutator, having the segments thereof diagonally disposed, a rotating brush revolving about said com mutator, and a centrifugal governor, operated by said engine and connected to said brush, so as to move over the said stationary commutator, so as to vary time of ignition of the explosive mixture in the cylinder of said engine, substantially as described.

7. In an electric controlling and starting device for gas-engines the combination with suitable Uniting-circuits, a storage battery charged by the engine and means for applying the power thereof to the engine-shaft, of a three-directional controlling-lever and connections whereby upon a movement thereof in one direction power is accumulated for starting the engine, by movement in another direction the ignition-circuits are thrown in, and upon movement in an opposite direction to the first movement the power accumulated in the storage battery will be applied to the engine-shaft for starting.

8. In an electric controlling and starting device for gas-engines the combination with suitable igniting-circuits, a storage battery charged by the engine and means for applying the power thereof to the engine-shaft of a controlling-handle capable of rocking about a pivot at right angles to its longitudinal axis and also movable about said longitudinal axis, and connections whereby when the handle is rocked in one direction power is accumulated for starting, when the handle is rocked in the opposite direction the accumulated power is applied to the engine-shaft for starting, and when the handle is moved about its longitudinal axis the ignition-circuits are thrown in or out.

9. In an electric controlling and starting device for gas-engines the combination of a storage battery charged by the engine and means for applying the power thereof to the engine-shaft, of a sparking igniter in circuit with the storage battery, an auxiliary ignition-battery also in circuit with the igniter and storage battery, and a controlling-lever and connections whereby movement thereof in one direction accumulates power for starting the engine-shaft, movement in the opposite direction applies the power accumulated to the engine-shaft, a third movement throws the storage battery onto the igniting-circuit,

IOC

and a fourth movement throws the auxiliary battery onto the igniting-cirouit.

10. In an electric controlling,` and starting device for gas-engines the combination of a Storage battery charged by the engine and means for applying` the power thereof to the engine-shaft, of a sparking igniter in circuit with the storage battery,an auxiliary ignitingbattery also in circuit with the igniter and Storage battery, a controlling-handle capable of rocking;` about a pivot at right angles to its longitudinal axis and also movable about said longitudinal axis, and connections whereby rocking;` the handle in one direction accumulates powerfor starting, rocking it in the opposite direction applies the accumulated power to the engine-shaft, movement in one direction about its axis throws the storage battery onto the igniting-eircuit and movement in the opposite direction throws the auxiliary battery onto the igniting-circuit.

l1. In a gas-engine the combination with a sparking,` igniter of a storage battery charged by the engine and an auxiliary ignitingbattery, both in circuit with the igniter and a single lever for throwing either the storagebattery current or the auxiliary-battery current onto the igniter at will.

12. In a controller for gas-engines the combination of a storage battery charged by lhc engine, means for applying` the stored charge to the engine-shaft for starting, a variable rheostat, ignitinwcircuiis including a sparking igniter, the storage battery and an auxiliary uniting-battery, a controlling-handle movable over the rheostat and capable o' rocking movement in two directions and axial movement in two directions, and connections whereby the rocki ngz movement introduces all the gradations of resistance beth in energizing and discharging the storage battery, and the .axial movement, according to its direction,

throws ihe storage battery or the auxiliary battery into circuit with the sparker.

Signed at New York, in the county ol New York and State'of New York, this 13th day of March, A. D. 1900.

FREDRICK A. LA ROCHE.

iVitnesseS:

GEO. M. MAoWILLi/xn, C. H. SCHUM.

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