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aid of a gentle heat. To the solution, while still hot, add 2 ounces by measure of alcohol, continuing the heat till reaction commences, when the nitric acid oxidises part of the alcohol to aldehyde and oxalic acid, becoming itself reduced to nitrous acid. T'he last-named acid in its the alcohol, the result being the production of nitrous ether, fulminic acid, and water. From the hot liquid the fulminate of silver is slowly deposited in the form of small, white, brilliant crystalline plates, which should be washed with a little cold water, and spread upon separate pieces of filterpaper, in portions not more than a grain or two each, after which they are left to dry in a warm place. When dry the papers are gently folded up and preserved separately in a box or bottle, this being the only safe mode of keeping the salt. It is one of the most dangerous of all chemical substances to handle, and explodes when heated, or when rubbed or struck with a hard body, or when brought in contact with concentrated sulphuric acid, with an enormous force, owing to the sudden disengagement of a large volume of gaseous matter, leaving the inetal reduced.

When fulminate of silver is digested with caustic potass, one half of the oxide is precipitated, and a compound is produced which resembles the neutral salt of silver, and detonates with a blow. This is sometimes used for the manufacture of anticorrosive percussion caps, but it has very little advantage over the

Fulminate of mercury, which is prepared by a process very similar to that described for fulminate of silver. One part of mercury is dissolved in twelve parts of nitric acid, specific gravity 1:37, the solution being mixed with an equal quantity of alcohol; gentle heat is then applied, and if the reaction becomes very violent, it may be kept down by the addition of more spirit as required. A large volume of carbonic acid, nitrogen, nitrous and aldehyde, and red vapour is disengaged, and the hot liquid deposits the fulminate of mercury, which may be purified by solution in boiling water and re-crystallization. It explodes either by friction or percussion, and when fired burns with a sudden and alınost noiseless flash if kindled in the open air.

To form the mixture which is used in the ordinary caps,

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sulphur and chlorate of potass (or more frequently nitrate of potass) are mixed with the fulminate of mercury, and the powder being pressed gently into the cap, is secured there by a drop of varnish.

Chlorate of potass and sulphur are sometimes used without fulminate of mercury, or silver. Equal parts of these two substances are carefully prepared, and mixed together without any friction between hard substances, which would cause an explosion. The mixture is then pressed into the caps and secured as before described. Caps so prepared are, however, very uncertain in their explosion, and they are also highly corrosive in the action of their residuum on iron. The Government caps are filled with a composition consisting of chlorate of potass, 6 parts; fulminate of mercury, 4 parts; and powdered glass, 2 parts.

Whatever substance is employed it should be protected externally by a copper cap or disk, and it should also be covered with a layer of some varnish, which will defend it from the effects of the atmospheric air.

Messrs. Eley and Joyce are the only two makers of caps in England, independently of the Government, and it would be hard to say which is entitled to the pre-eminence, for the productions of either may be taken as approaching so nearly to perfection as to leave little to be asked for. At present they each make two kinds-one small, and adapted to ordinary guns, and the other larger and stronger, as ordered by the Government, and suited for rifles, especially when a cartridge paper has to be pierced. Eley's caps are coated with a metallic foil, which is intended to prevent decomposition by contact with air or moisture, while those made by Joyce are covered with “a highly waterproof substance, burning with the same facility as the powder itself, and in no degree detracting from that certainty and sharpness of fire, as well as anti-corrosive property, so necessary for the convenience and comfort of those who use them.” These words are from Mr. Joyce's circular, but I can speak to their correctness from experience. The price of the sporting caps by either of these makers is ls. 6d. per box, containing 250, or 58. 6d. per 1000. In all cases the caps ought to fit the nipples with which they are used, and in ordering a lot

12 | 13 | 14

the nipple should be sent to the gunmaker. The Birmingham and London sizes do not correspond, the following being the relative sizes of Mr. Eley's with the Birmingham scale:Eley's .. Birmingham

50 | 51 & 52 53 & 54 | 55 & 56 | 57 | 58 Where there are two numbers of the Birmingham sizes corresponding with only one of Eley's, it is in consequence of two of their numbers being of the same size, varying only in the length of the caps.

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CHAPTER III.

ON THE VARIETIES OF PROJECTILES AND THE

SUBSTANCES USED IN AID OF THEM.

ALL SPORTING PROJECTILES MADE OF LEAD-EITHER CAST OR PRESSED

AS IN BALLS, OR DROPPED FROM A HEIGIIT AS IN SHOT-SHAPES OF BALLS-SIZES OF SHOT-WADDING AND PATCHES-CARTRIDGES.

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ALL SPORTING PROJECTILES MADE OF LEAD. Lead is the substance of which all sporting projectiles are made, whether they are used in the size of a four-ounce ball or in that of dust shot. There is some difference in the quality of this metal, which is often alloyed with zinc, when its specific gravity is greatly reduced, though it is somewhat harder than the pure metal. The latter should, however, be preferred, as weight will have more effect than hardness in producing penetration. The price of lead is about 3d. to

. 31d. per lb. 3.

Balls are cast of various shapes and sizes in moulds which are generally made to open like a pair of pincers. In order to avoid the slight variations which are found to exist in all cast bullets, Mr. Greenfield has invented a simple machine, by which each cylindro conical ball is driven through a gauge by means of a lever. It is a very useful contrivance for muzzle-loading rifles, in which an exact fit is required. These forms of bullets vary almost indefinitely, every con

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ceivable shape having been tried; but this will be better considered in connexion with the rifle itself. A spherical ball used with a smooth bore is now seldom adopted for any kind of shooting, as its flight beyond one hundred yards is so uncertain that no reliance can be placed upon it.

Shot are small globular pieces of lead, of various sizes from rather less than a quarter of an ounce each to such a small diameter as to take nearly two thousand to make up

that weight. Messrs. Parker and Co., of London, are the chief makers in the south, and they have the following sizes, which are each said by Col. Hawker to contain the annexed number of pellets in the ounce :

MOULD Suot.
L.G. contains in the oz.

5} pellets.
M.G.

8] S.G.

11 S.S.G.

15 S.S.S.G.

17

PATENT DROP Shot.

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99

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99

A. A. contains in the oz.

40 pellets. A.

50 B.B.

58 B.

75 1

82 2

112 135 177 218 280

341 8

600

984 10

1726 Dust shot variable.

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These numbers will, however, be found to vary considerably from those of which an ounce of the shot as now

sold is composed, depending a good deal on the quality of the lead used, the specific gravity of which is scarcely ever the same.

I have counted the pellets in an ounce of shot used at the recent gun trial, and find them to be 290. The makes of other firms are also differently sized, as will appear from the experiments of a writer in the Field, under the signature “G.,” who says:

“Most people suppose that an ounce of No. 6 shot is the same all over the world, and so did I until I had the curiosity to compare the contents of several bags of shot and cartridges by different makers. The following is the result:

NUMBER OF SHOT CONTAINED IN OXE OUNCE.

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No. 5. No. 6. No. 7. No. 8. From Messrs. Parker and Co., London

326

537 Messrs. Cox and Co., Derby

230

335 Messrs. George and Co., Bristol

219 298 421 Eley's " Universal" Cartridge

180 Joyce's " Cniversal” Cartridge 220

326 Eley's Patent Muzzle-loading Cartridge Hall's Patent Cartridge

270

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249

“The shot was very carefully weighed in a fine pair of scales and counted, and in most instances an average of three ounces taken. I have no doubt that my friends, the gunmakers in London, make their trials with Parker's shot; while I, living in the West of England, made mine with the shot manufactured at Bristol."

There is evidently some mistake in some of these numbers, as there is no make of No. 6 which will contain 326 pellets in the ounce. Cartridge-makers all use the full size of shot, because their object is to increase the distance at which they can kill, and not so much to improve the pattern. I have counted as few as 260 pellets in Eley's, and 270 in Joyce's No. 6. I have also often found mistakes in the numbersthus, cartridges marked No. 5, have contained No. 4 or No. 6; and in this way it is easy to see that the error has arisen in the instances where “G.” has found 326 pellets in an ounce of No. 6, which really was No. 7, though probably marked No. 6.

The best size for general use, and that almost universally

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