SMITH & STETSON.

Shell-Fuse.

No. 34,788 Patented Mar 725, 18 62.

. 1 Nrrnn warns CHAS. XV. SMITH AND THOS D.

s rs'on, or new roan, N. Y.

P ovEMENT INTHE Process or concussion-shares.

k Specification forming part 0t Letters Patent No. 3%,?88, datedllriarch 25, 1862.

.10 air; whom it may concern:

Be it known that we, CHARLES W. SMITH. and Trronas D. Srnrson, both of the city, county, and State of New York, have invented a certain new and Improved Percus- I sion-Fuse; and we do hereby declare that the following is afull and exact description there of, reference being had to the accompanying drawings, and the letters of reference marked thereon. D

Our invention relates to that class of explosive projectiles moving point foremost, like those commonly known as percussion shells;

and it consists in certain means for preventing the premature explosions to which such projectiles have hitherto been peculiarly liable.

. Figure 1 is a full-sized sectional View of a- Hotchkiss percussion-shell with our inventhe center of the shell. I l

The plunger G, FigLl, is constructed in a cylindrical form, of a diameter somewhat less than that of the cavity in whichv it is placed, and it is made of leather, what is better, a mixture of lead and tin in about equal parts.

On the front end of the plunge s screwed a metallic nipple, E, bearing apercussion-cap, D, Projectiles having percussive mechanism of a form similar to oursare well known; .butthe material employed in oursfis novel, and the effect differs widely in one important particular from that of any before known. Previous to the date of our invention p'lungers' .were made wholly of iron orfbrass, and the theory oi their action was as follows: At the moment of discharge. from the gun they were expect-ed to slide back to the rearfof the cavity. if they were not already there, and remain in thisposition until the time of impact. At this mo- 'ment, the forward motion of the ball being retarded suddenly, they were free to fly forward of their own inertia,and thus'explode by striking it against the screw. 1 The ho; g generated by the explosion of the cap would rush backward through theaperture in the center .nf the plunger, igniting the powder in moment of discharge. 'lhccause of this :may be explained asfollows: There are/few, if any, substances which do not possess a certain amount of elasticity," and when two elastic bodies are brought into'violent contact they will recoil with a force varying directly in proportion to the violence of the impact and the elasticity of the material of which they are composed. Iron and brass possess this property in a high degree. When, therefore, the shock of the explosive is communicated to the body of the projectile, this, in turn, strikes against the plunger; producing a recoil which throws it forward within the cavity with a velocity which exceeds that of the shell, and causes'it immediately to strike against the screw with a force often suiiicient to explode thecap; but, although all bodies'are to a oer-.-

tain extent elastic, there is a class of sub-' stances of considerable tenacity, whose elasticity is so feeble as to he almost inappreciable. Such are lead and various alloys known inthe arts as soft metal. These are found, when tested by their power of resistance to a'blow as violent as that imparted by the explosion of gunpowder, almost devoid of this property.

WVhen he plunger, therefore, is made of plastic or soft m erial, like lead, or an alloy such as we have described, the effect of the shock is to upset it, imparting to it a form resembling that shown in Fig. 3, and if it dart forward at all, if the material be sufficiently soft, it will never be with force, enough to explode the percussion-cap and thus our invention fulfills t-h'e conditions'of exploding-the shell at the right moment and avoiding the liability of premature discharge. The action of a plunger made like Fig. 2 is similar 'in its nature. There the body of the plunger E isof cast-iron or brass,

bearing a nipple and cap upon its front, and resting at the rear upon a short lead or other soft-inet-al'tube-Ga cast with corrugations in -itslongitudinaisection,asrepresentedinthefigs.

ure. WVhe'n the shell is fired, the corrugations are deepened, the tube G beeomingshorter, and the shock is thus cushioned or deadened before it reaches the plunger. Many other modifications of this intention .will readily occur toaskillful mechanic. The plunger may be made of iron, with a collar resting upon the shoulders a a, at the ,rear of th the shell; but in practice it was found that these shells would frequently explode at the aperture, the body of the plunger passing through the narrow aperture into the interior of the shell. One or more washers of lead may be then slipped upon the plunger, and thus in; terposed between its collar and the shoulders a a, thus serving to deaden the shock. Another method is to line the cavity B with lead; either throughout its whole extent or simply in the rear, making the plunger of anyeonvenient inel'asti or soft materialbes'o interposed between the inertia of the plunger and the transmitt'ed shock of the explosion'as to deaden the shock by yielding to a permanent change ofform, it is a mere modification of our invention.

What we claim, therefore, as our invention, and desire to secure by Letters Patent, is Theiusef of soft material"suoh aslead o ritsjg equivalentin' theflperenssive nieehanism, ofj' shells, substantially in the mander;- and'so as v to produce the effect herein set forth. I .In testimony whereof we-have-hereunto set, our han'ds in the presence of two subscribing witnesses., Y materialyand if by-anymeansa cushion of OHAS. W. SMITI L T THOMAS Di STETSON.

Witnesses:

HARRY M. ConLYER, D. W. STnTsoN.