US1043890A - Recoil-checking mechanism for ordnance. - Google Patents

Description

P. B. YINGLING.

BECOIL GHEGKING MEGHANISM POR ORDNANGB.

APPLIoATIoN FILED MAY 19, 190e.

1,043390. Patented Nov.12,1912.

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(lill/[KIM a F. B, YINGLING.

BBGOIL GHEGKING MBCHANISM POB ORDNANGE.

APPLICATION FILED MAY 19, 1906.

.Patented Nov. 12, 191.2.

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FRANK B. YINGLING, 0F VQTASHINGTON, DISTRICT OF COLUMBIA.

RECOIL-CHECKING MECHANISM FOR ORDINANCE.

" and to so proportion and arrange the parts that the stress during the recoil, occasione/l by ring the gun at any elevation, shall not exceed that required to properly regulate the minimum length of recoil permitted, but

will have, throughout such recoils, similar characteristics to that of the minimum recoil. That is, diagrams of the required pressures 'in the recoil cylinder, during different lengths of recoil,have similar out-- lines, instead of, for instance, a regular outline for one length of the recoil andan irregular one for other lengths. The resistance due to the fluid in the recoil cylinder plus the resistance of the counter recoil springs during recoils is maintained pracv tically or substantially uniform throughout each length of recoil, or uniformly decreases a small amount as desired, but this resistance becomes less as the length of recoil increases from the minimum permitted, since the checking devices .are so proportioned for the different lengths permitted, that they "operate inaccordance with the retarded velocit-ies of the recoiling parts at each instant of recoil.

The laws, formula and coeicients neces-v sary in proportioning the parts of arecoil carriage fora particular slze of gun, projectile, etc., foca set of speclfications are well known to those proficient in the design of such-constructions so that it is notdeemed necessary to elaborate a method of finding the exact shape or dimensions of the checking means. Well known treatises and notes on ordnance 'construction heretofore vpublished are available for determining suitable Specification of Letters Patent.

Application led May 19, 1906. Serial No. 317,845.

Patented Nov. 1 2, 1912.

dimensions and proportions of such embodiments as I illustrate which have a plurality of recoil lengths.

After the theoretically correct dimensions of the recoil control devices for a particular gun and carriage have been determined, it 1s frequently necessary, after constructing the parts, to experiment and determine under actual conditions of service just what the dimensions must be to give a uniform resistance or a slightly uniformly decreasing resistance to the gun throughout a particular length of recoil because of some coefficients that enter the formulas which are usually different for various "forms of recoil checking devices.

In connection With this embodiment of my invention for recoil checking devices operating as described, reference is made to my application filed December l, 1904, and to my application filed December 8,1905, of which this is a development.

The invention 'is particularly applicable to siege or other guns'that are desired to be fired at either high or low elevations.

Various forms of fluid pressure recoil checking mechanisms have been heretofore proposed for automatically varying the length of Vrecoil inA accordance withehangcs in the elevation of the gun. One of 'the plans proposed includes the employment of means for varyingthe size of a single set of ports through which the braking fluid can pass from one side of a piston to the other. Another class provides a different uid passage or orifice for each of the various lengths 0f recoil permitted. lMechanism of the first provide a simple and e ective mechanism.

which can be readily applied to any form of ordnance, and will regulate the recoil at any elevation.

The invention is illustrated in the accompanying drawings, in which,

Figure l illustrates diagrannnatically the general forms of orices or fluid passages required for controlling the minimum and maximum or other recoils, and the principle of the present. invention; a being the contour of the orifice for minimum recoil; l being the contour of the orifice tor maximum recoil: a a cross section of either orivtice a or b; and c represents the difference between the orifice a. and orifice I), which when used as un auxiliary orifice directly with orice a would produce the same result. as when orilicev b acts alone. Fig. 2 is a longitudinal sectional view through one form olf-apparatus constructed in accordance with the present-invention; Fig. 2a is a sectional view showing the valve in the position occupied at the beginning of the'counter recoil movement; Fig. 3 is a sectional View on the line 8-3 of Fig. 2; Fig. 4 is a longitudinal sectional view through a different form of recoil mechanism embodying the invention; Fig. 4a is a detail view of one of the guide bars; Fig. 5 is a section on the line 5 of Fig. 4; Fig. 6 is a section on the line 6 of Fig. 4; Fig. 7 is a view onv the line 7 of Fig. 4; Fig. 7 is a view on the line. 7 of Fig. 4; Fig. 8 is a View, partly in section and partly in elevation, illustrating the devices for adjusting the valve of the auxiliary fluid passage; Fig. 9 is a transverse sectional view;`Figs. 10 and' 11 are longitudinal scctional views of other embodiments of the invention.

Referring to the drawings, and particularly to Fig. 1, a illustrates the general form of orifice or fluid passage which would be used for regulating and controlling the minimum recoil permitted a piece of ordnance, and Z1 represents the general form of orifice or passage required for properly controlling the maximum or other recoils each being the bottom of a groove as a. According to the present invention, it is proposed to use the orifice or passage represented by a for all lengths of recoil and to supplement the same at proper times by an auxiliary passage or orifice of such character and capacity that the orifice or passage represented by I will be effective during the maximum or other recoils. lBy comparing the curves a b, it is found that the difference between `them, or the amount of in-, crease of the orifice or passage represented by curve a that must be provided to properly control the maximum or other recoils, is represented by c, and by providing means corresponding respectively to the curves a, c and properly adjusting said means it is possible to accurately control bot-h the minimum recoil and other recoils exceeding the minimum. That is, for properly controlling each length of recoil exceeding the minisimilar to those produced by. a alone, al-` though oflower intensity, since as orifice a. is the minimum in capacity and in length the resistances will necessarily be ot' inverse ratio and consequently the maximum required to absorb the given energy of the` recoiling gun. Y

Referring to Figs. 2 and 3, there 1s shown a device embodying the orifices a and cv arranged to be Aoperative or'the minimum and maximum recoils permitted, in which 1 is a bar connected to the fluid cylinder 7 at its rear end. On the bar l grooves 2 and 3 are formed, grooves 2 corresponding t0 the orifice curve a, and grooves 3 correspending to the orifice curve c. Wit-hin the cylinder 7 is arranged a piston rod 5 and a piston 6 enveloping the bar 1. The forward end of the piston rod 5 is attached to a fixed part of the gun carriage While cylinder 7 is attached to the gun 12 and recoils with it. Within the piston head 6 are arranged tluid passages 8 which connect with the grooves 2 and 3 and thereby afford communication forA the liquid to the rear side of the piston. 0n the rear side and within the piston is formed a cavity, and in this cavity is arranged a valve 9 keyed to the piston 6; but free to be pressed to the rear by the fiuid pressure, and forms part of the passages 8,- but upon counter recoil of the gun the returning fluid presses the valve 9 forward, and restricts the passages 8. The valve 9 is formed in a manner that sec- .tions extend to cover over and uncover the grooves 3 in bar 1, by a rotation of the piston rod 5, and the piston 6 with valve 9, thus exposing grooves 3 to the action of the braking fiuid or closing them off as required by the elevation. On the forwardv end of the piston rod 5 is fixed a lever or gear 10 to which is attached any suitable gearing or mechanism, as later described, for rotating the valve 9 upon a change in the elevation of the gun. The action would be as follows, assuming the gun to be fired at the highest elevation the valve 9 would be so turned thatl the grooves 3 are closed, and only grooves 2 are operative; this results in the minimum length of recoil, when the grooves 2 pass to the rear under passages 8, as the elevation lof the gun is decreased a predetermined amount the valve 9 is turned to open the grooves 3 and the combined orifice area of grooves 2 and 3 are operative as they pass under passages 8, thus lengthening the recoil to the maximum, with accurately controlled similar resistammasso ances for the maximum and minimum lengths of recoil. The counter recoil will be controlled by the valve 9 moving forward and restricting passages 8.

Referring to Figs. 4 to 7a, wherein there is illustrated a recoil mechanism, embodying the principle of the present invention, of that type in which the piston is connected with the gun to move longitudinally of the relatively stationary fluid cylinder 7, it will be seen that there are arranged within the cylinder two disks or abutments 9a, 9 between which the piston 10 operates. The stem l1 of the piston extends through the abutment 9a and through a suitable stuffing box at the rear end of the fluid cylinder, and is suitably connected with the gun 12. The abutments 9, 9 are connected b rods or bars 18 which constitute a gui e for the piston and also as a means for bracing said abutments. As shown in Figs. 6 and 7, the rods or bars 13 are of such cross sectional form as to constitute, with the. openings in the piston head through which they extend, a fluid passage of the capacity of a in Fig. 1 through which the body of 4fluid conned between said abutments may pass from one side of the piston to the other during recoil and counter recoil. It will be seen that the a'butments or disks 98,9, divide the fluid contained in the cylinder 7 into two bodies, on the pressure side of the piston the main or principal body, which is operative to check the recoil at all elevations o the gun, being confined between said abutments, while the auxiliary body of fluid is confined within the spaces between the ends -of' the cylinder and the abutments, said spaces being connected by an auxiliary passage 14 with which cooperate two valves 15, 16. 4

VWhenthe gun is at its maximum elevation, the parts above referred to will occupy the relative positions shown in Fig.' 4. That is. the auxiliary passage 14 will be entirely closed by the valve 15 and therefore during recoil the only passa-ge through which the braking iiuid can pass from one side of the piston lto the other is that provided by the guide bars 13 and the openings in the piston head through whichV said bars pass. This is of such dimensions that the recoil will b'e properly checked in the minimum distance-permitted by the mechanism,

,since the orifice is of the capacity of a in Fig. 1. The body of fluid to the rear of abutment 9a, or the auxiliary body, serving at this time to simply transmit the pressure to the rear cylinder head.

When the elevation of the gun is lowered to a predetermined extent the valve 15 will be automatically adjusted to open the'auxiliary passage 14` and when the parts are in such condition, a longer recoil will be permitted. Under 'such conditions, the

operation of the piston and guide bars 13 will be similar to that during the minimum length of recoil, but as the passage 14 is open a portion of the auxiliary body of fluid will pass from one side of the piston to .ment of the abutments relative to the cylinder 7 is dependent on the extent of opening of the Valve 15 and the amountof pressure created by the movement of the piston toward the abutment- 9a. When said valve is moved outward to fully open the auX- iliary passage 14, the abutments will move rearward during recoil until the rear abutment 9a closes the port 14'a through which the passage 14 communicates with the rear portion of the cylinder 7, the piston having meantime reached the limit of its movement alo-ng the curved bars 13, and therefore the maximum length of recoil will occur.

The introduction of the iuid cont-rolled abutment renders it possible to obtain resistances throughout the different recoils, with sensibly similar characteristics to those of the minimum recoil, by using an auxiliary orifice that opens to increase the recoil length, but that remains constant throughout the time of the recoil, since the orifice curve a is operative throughout the length ofeach recoil.

During counter recoil, or while the gun is being returned to its in battery position, which movement may be eiected by suitable springs or other means commonly employed, the flow of fluid through the auxiliary passage 14 will be cont-rolled by the spring pressed valve lwhich restricts the return flow of the fluid, and the force ofthe counter -recoi'l may be further cushioned by suitable plungers 17, 18 to bring the gun to rest.

c Any suitable means may be employed for shifting or adjusting the valve 15. As shown in Figs. 4 and 8 the rod or stem 19 thereof is connected with one arm of a slotted lever 20 journaled in suitable bearings below the cradle or gun support and the other end of said shaft is provided with an arm 21 which, as the elevation of the gun is raised, will contact with a stop 22 on the frame of the gun carriage. Continuing, the

elevation of the gun will cause the slotted suitable guide 23 is provided for the end of the arm 21 said guide having a deected section 24 into which said arm extends when the elevation of the gun has brought it into contact with the stop 22. The stop 22 will be properly located with reference to the arm 21 to insure that the valve 15 will be adjusted to provide the desired length of recoil at a particular elevation. It 1s possible by this construction to permit the gun to have a maximum extent of recoil until the elevation of the gun has nearly reached such a degree that the breech thereof will strike portion of the gun trail, as for instance, a cross piece or brace 25, when the engagement of the stop 22 and arm 21 will actuate the valve to -reduce the length of recoil. The auxiliary iiuid passage may be formed in a different manner and the area or extent thereof varied by means different from those just described, which will close olf the orifice at all lengths of recoil.

In Fig. 10 is shown a slightly different arrangement of parts for this purpose. Referring to said ligure it will be seen that the piston l0 is arranged within a cylinder 26 having a port 27 at one end; and the auxiliary passage 14a for the braking fluid is formed between said inner cylinder 26 and the main fluid cylinder 7", the area of said passage being controlled by a valve formed by a tapered bar 28 having on its lower face a rack with which engages a pinion 29 that is rotated as the elevation of the n is varied. This can be accomplished by the shaft provided with the arm 21 previously described. As shown a longitudinal groove is preferably formed in the side of the cylinder which groove is of the same width as the groove in which the tapered bar 28 slides. This clearance groove insures a balancing of t-he inner cylinder preventing friction due to pressure which acts to press the cylinder against the wall of the outer cylinder. With this construction the operation during recoil will be the same as that of Figs. 4--7'a previously described in that the piston 10EL moves to the rear wit-h the gun 12. When the parts are in the position shown the auxiliary iluid passage 143L is entirely closed and the minimum length of recoil results, this being controlled by the movement of fluid in the inner cylinder 26 from one side of the piston headv to the other through the space around the piston 10 which corresponds to the orifice a of Fig. 1. Y The inner cylinder 26 remains stationary since the liquid in the rear part of cylinder 7'i cannot escape, and only acts to transmit the resistance to the forward head of cylinder 7a. When the elevation of the gun is lowered a predetermined extent the pinion 29 will be actuated and adjustthe valve to open the auxiliary fluid passage more or less and thereby permit Huid to of recoil. The area of the orifice 14 is'pro- 1 portioned and maintained by the movement' of the bar 28 longitudinally so as to allow the inner cylinder 26 to recoil sufficiently to close the oriicc 14* at the end of recoil,

since the piston 10* has simultaneously rei coiled to the end of its allowed movement within the cylinder 26. The recoil of the piston 10'L relative to the cylinder 7 being the total recoil, which equals the recoil of the piston 1()l1 within cylinder 26 plus the recoil of the cylinder 26 within cylinder 7, the resistance of such recoils Vbeing similar to that of the minimum recoil. In counter recoil the Huid is restricted by the valve 16a, as in the previous form, thus controlling the return of the gun into battery.

yl'n the foregoing description of this form in Figs. 4-10 ithas been assumed that the cylinders 7, 7, were relatively stationary and that the piston was moved rearwardly therein during recoil, being connected with the gun. The invention in this form is,

however, equally applicable to recoil check-l ing mechanism of the opposite character or type, namely that in Vwhichthe piston is held stationary during recoil'and the -luid cylinder connected with the gun moves rearwardly during recoil, as illustrated in Figs. 2-3. Such an embodiment of the invention is illustrated in Fig. 11, referring to which, it will be seen that the stem or rod 11b of the piston 6* is provided with a chamber that communicates through ports 30 with the inner cylinder 31 in which is contained the auxiliary or supplemental body of braking fluid that is operative only when the length of recoil exceeds the minimum. Into said chamber in the piston 6 and rod 11b extends a bar 32 connected to the rear end of the main fluid cylinder 7b, said bar having grooves 33 formed therein, and adapted to communicate with the ports 30 in the pisy ton 6a when the latter is properly adjusted. The ports 30 are adjusted over the grooves 33 by rotation of the piston rod 11b by means of suitable gearing 34 connected to operate, as previously described. when the lgun is elevated or depressed. The grooves 33 are of uniform area and have the same function as the valve 14 and 14.a of the two previous forms, being closed or inoperative when the gun is operating at the minimum recoil. Fluid orifices are formed between the outer cylinder 7 b andthe inner cylinder 31` which have a capacity, as a in Fig. 1, being for the minimum recoil. A movement of the gun Vin recoil causing the outer cylinder to close off said orifices .and maintain he resi'stancesince it will be understood hat 'both cylinders 31 and 7"' are iilled with he braking fluid and when the parts are djusted for the length of recoil, he piston will be held in a xed position elative to the inner cylinder 3l as the ports v therein do not communicate with the rooves 33. Under these conditions, the iner cylinder 31 and the fluid therein become 1 eifect a part of the' piston and remain :ationary While the outer cylinder 7b moves earwardly thereover during recoil.

As the elevation of the-gun is lowered to ich an extent that it is desirable to increase 1e length of recoil, the piston will be ro- Lted by the gear 10t1 and suitable connecons to bring the ports .therein into com- Lunication with the grooves 33, and during zcoil with the parts in lthis position the uid contained in the inner cylinder 31 will e permitted to iow through said ports 30 1d lgrooves 33 to the rear of the piston 6a 1d 'therefore' said inner cylinder 3lv will love rearwardly simultaneously with the ain cylinder "ib and gun l2 and the length E recoil will be increased.

It will be seen that each of the several )rms of recoil mechanism illustrated emloy the same principle. That is, in each lere is a passage for linid from one side of le piston .to the other which is operative at l recoils or elevations of the gun, and in ldition, an auxiliary passage or passages Lhe dimensions of which are automatically tried `by changes in the elevation of'the m, and are such that the resistances are roperly regulated and have characteristics =nsibly similar to the resistance of the minif .um recoil) are provided when the recoil to be of other than the minimum length. ny of the forms of recoil mechanism illusated may be employed, the particular one `lected depending on the degree of refineent of control which is desired.

It will be observed that to obtain the eifect oritlce curve Z), Fig. 1, it is necessary to nploy with orifice curve a, which is ixed 1d used for all lengths of recoil an addianal orilce curve represented by c. When lch orifice c is employed directly with ori- :e curve a, the form of orifice c increases 'om the origin to the end of orifice curve a, 1d from this point to the end decreases, .'oviding means are not introduced for peritting the operation of orice curve ai .roughout the length of the recoil required, which case a constant auxiliary orifice ,n be employed during each recoil exceeding .e Y By Vintroducing means as .own this can be accomplished'.

What I claim is,- 1 l 1. In aiiuid pressure recoil checking mechusm for ordnance, the combination with a lid cylinder, and a piston'in said cylinder,

of means providing a curved longitudinal ity that the flow of iuid therethrough will properly check the recoil when the gun is 'at its maximum elevation, means for providing a supplemental or auxiliary iiuid passage from one side of the piston to the other, and means for automatically varying-the dimensions of said supplemental passage in accordance with variations in the elevation of the gun, for the purpose described.-

2. In afiuid pressure recoil checking mechanism for ordnance, thecombination with a fluid cylinder, and a piston in said cylinder, of means providing a curved longitudinal fluid passage from one side of the piston to the other that is operative at all elevations of the gun, said passage being of such capacity that the flow of iiuid therethrough will properly check the recoil when the gun is at its maximum elevation, means for providing a supplemental or auxiliary fluid passage from one side of the piston to the other, and means for automatically increasing the capacity of said supplemental passage as the elevation of the gun is reduced a predetermined extent from the maximum, for the Y purpose specified.

3. In afluid pressure recoil checking mechanism for ordnance, the combination with a fluid cylinder, and a piston in said cylinder, said piston and cylinder being relatively movable during recoil, of means dividing the fluid in the cylinder into two tandem bodies on the pressure side of the piston,

means preventing movement of one of said bodies of :duid relative to the cylinder during recoil when the gun is at vits maximum elevation, and means for permitting fluid from both said bodies to flow from one side of the piston to the other during recoil when the elevation of the gun is reduced a redetermined extent, for the purpose speci ed.

4. In aiiuid pressure recoil checking mechanism for ordnance, the combination with a liuid cylinder, and a piston in said. cylinder, said piston4 and cylinder being relatively movable during recoil, of means dividing the fluid in the cylinder into two tandem bodies on the pressure side of the piston, means for permitting fluid from the main fluid body to pass Irom one side of the piston to the other during recoil at allelevations of the gun, means for preventing fluid from the auxiliaryfluid body from passing from one side of the piston 'to the other during recoil when the gun is at a predetermined elevation, and means for permitting iuid/ from said auxiliary body to pass the pistonV when the elevation of the gun is re duced a predetermined extent, for the purpose specified.

5. In a fluid pressure recoil checking mechanism for ordnance, the combination with a fluid cylinder, and a piston in said cylinder, said piston and cylinder being relatively movable during recoil, of means dividing the fluid in the cylinder into two tandem bodies on thepressure side of the piston, and means for rendering one of said bodies inoperative when the elevation of the gun is raised to a predetermined extent, whereby the length of recoil can be automatically varied.

6. In ailuid pressure recoil checking mechanism for ordnance, the combination with a fluid cylinder, and a piston in said cylinder, said iston and cylinder being relatively mova le during recoil, of a body of fluid within the cyllnder adapted to cooperate with the piston and cylinder to check the recoil when the gun is at its maximum elevation, and an auxiliary body of fluid Within the cylinder adapted to coperatie with the main body in 'checking the recoil when the elevation of the gun is reduced a predetermined extent.

7 In a fluid pressure recoil checking mechanism for ordnance, the combination with a fluid cylinder, of two abutments mounted in and adapted to move longitudinally of said cylinder, a piston within the cylinder between said abutments, said piston and cylinder being relatively movable longitudinally of the cylinder, means connecting said abutments and coperating with the piston to provide a fluid passage from one side of the piston to the other, that is operative at all elevations of the gun, a supplemental valved passage for conducting fluid from one side of the piston to the other, which when opened permits said abutments to move longitudinally of the cylinder, and means for automatically varying the extent of opening of said supplemental passage in accordance with variations in the elevation of the gun, substantially as and for the purpose described.

8. In a fluid pressure recoil checking mechanism for ordnance, the combination with a fluid cylinder, of two abutments mounted in and adapted to move longitudinally of said cylinder, a piston within the cylinder between said abutments, said piston and cylinder being relatively movable longitudinally of the cylinder, means connecting said abutments and coperating with the piston to provide a fluid passage from one side of the piston to the other that is operative at all elevations of the gun, a supplemental passage through which fluid can pass from one side of the piston to the other, a valve for closing said supplemental passage, and means for holding the valve in position to close said supplemental passage when the un is at its maximum elevation and adjusting said valve to open said passage as the elevation of thevgun is reduced a prtdetermined extent, for the purpose specifie 9. In a f fluid pressure recoil checking Vmechanism for ord-nance, the combination of a relatively stationary fluid cylinder, a piston in said cylinder arranged to move longi-4 tudinally thereof during recoil, a curved longitudinal fluid passage, controlled by the piston and operative at all elevations of the gun, a supplemental passage through which fluid can flow from one side of the piston to I the other, a valve for closing said supplemental passage, and means for adjusting said valve to vary the extent of opening of said supplemental passage in accordance with variations in the elevation of the gun, for the purpose specified.

10. In a fluid ressure recoil checking mechanism for or nance, the combination of a relatively stationary fluid cylinder, a piston in said cylinder arranged to move longitudinally thereof during recoil, a curved longitudinal fluid passage, controlled by the piston, and operative at all elevations of the gun, a supplemental passage through which fluid can flow from one side of the piston to the other, a valve for closing said supplemental passage, and means for moving said valve to open the supplemental passage when the elevation of the gun is varied a redetermined extent, for lthe purpose speci ed.

11. In a fluid pressure recoil checking mechanism for ordnance, the combination of a relatively stationary fluid cylinder, two abutments mounted in said cylinder and dividing the Huid therein into two bodies, a piston mounted between said abutments and connected. with the gun, means for roviding a passage operative at all elevatlons of the gun for conducting the main body of fluid situated between said abutments from one side of the piston to the other during recoil, an independent passage for conducting fluid from the chamber between said abutments and the end of the cylinder from one side of the piston to the other, a valve for closing said auxiliary passage when the gun is at its maximum elevation, and means for automatically adjusting said valve to open said passa e to a greater or less amount whenl the e evation of the gun is reduced a predetermined extent, for the purpose speci- 12. The combination of a recoil mechanism provided with recoilchecking means, and means to control such checking means at each instant of recoil in proportion to the retarded velocity for the instant in question, substantially as described. l

13. In a gun mount, the combination of a recoil cylinder and piston rovided with a by pass, with means adapte to change said by pass in proportion to the changes in the retarded velocities of the recoiling parts at each instant of recoil, and thereb cause the pressure in the cylinder to remain substantially constant throughout the recoil, substantially as described.

14. In a gun mount the combination of a piston and recoil cylinder containing a ud and provided with a by pass, and automatic means adapted as the gun recoils to vary the exit of said iiuid through said by pass in accordance with the retarded velocities of the recoiling parts at each instant of the recoil, whereby the pressure in said cylinder remains substantially constant throughout the recoil, substantially as described.

In testimony whereof I aix my signature in presence of two witnesses.

FRANK B. YINGLING.

lVitnesses:

THOMAS HowE, ARTHUR L. BRYANT.

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