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coated with lead, which is applied by placing the shell in a mould and pouring melted lead round it.* The lead is allowed to percolate among the segments, so as to fill up the interstices, the central cavity being kept open by the insertion of a steel core. In this state the projectile is so compact that it might be fired through six feet of hard timber without injury, while its resistance to a bursting force from within is so small that less than one ounce of powder is sufficient to break it in pieces.

The segmental pieces act like the voussoirst of a bridge in fact, in strengthening the shell ; but are easily liberated, when they are very destructive. This same projectile can be used as a shell; by leaving out the bursting charge, as a shot; by arranging the fuze so as to burst it as it leaves the muzzle of the gun, as common case; or, lastly, by arranging the fuze to burst it just before reaching the object, as shrapnel

. Such simplicity of ammunition, which further enables one gun to fulfil all purposes of gun and howitzer, is of the very greatest advantage. Two descriptions of fuzes are used by Sir W. Armstrong; the one a percussion fuze for use when it is intended to burst the shell on striking an object; the other, a time fuze, to explode it at any given length or time of range, without its striking an object, as when used as case or shrapnel. It must be remembered that the gun is a breech-loader, and that there is no windage by which the gas or flame of the powder can, as with ordinary guns, get round the shot and ignite the fuze. The latter has, therefore, to ignite itself at the instant of discharge. This is effected by a percussion arrangement; the rest of the fuze being very much on Breithaupt’s principle. Sir W. Armstrong thus describes his fuze :

The body of the time fuze (fig. 3) is made of a mixture of lead and tin cast to the required form in a mould. The fuze composition is stamped into a channel forming nearly an entire circle round the body of the fuze, and is afterwards papered and varnished on the external surfaces. As the shell fitted accurately into the gun, there was no passage of flame by which the fuze could be ignited. The effect is, therefore, produced in the following manner :-A small quantity of detonating composition is deposited at the bottom of the cylindrical cavity in the centre of the fuze, and above this was placed a small weight or striker, terminating in a sharp point presented downwards. This striker is secured in its place by a pin, which, when the gun is fired, is broken by means of the vis inertiæ of the striker. The detonator is then instantly pierced by the point, and is thus fired. The flame

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* Mr. Bashley Britten's plan of joining the lead to the iron by an interior skin of zinc is, we believe, now adopted.

+ The voussoir is the technical name given to the wedge-shaped stones which constitute an arch.

thus produced passes into an annular space formed within the revolving cover, which rests on the upper surface of the fuze composition ; and from this annular space it is directed outwards through an opening, so as to impinge on and to ignite the fuze composition at any required part of the circle. The fuze thus ignited burns in both directions, but only takes effect at one extremity, where it communicates with a small magazine of powder in the centre. The fuze is surrounded by a scale-paper, graduated to accord with the elevation of the gun, so that when the range of a distant object is found by trial, it is only necessary to turn the igniting aperture of the cover to the point on the fuze scale corresponding with the degrees and minutes of elevation on the tangent scale.

The concussion fuze (fig. 4 ) is on nearly the same principle. A striker with a point presented upwards is secured in a tube by a wire fastening, which is broken on the firing of the gun ; the striker being thus liberated, recedes through a small space, and rests at the bottom of the tube ; but, as soon as the shell meets with any check in its motion, the striker runs forward and pierces the detonator in front; by which means the bursting charge is ignited.

The Whitworth gun may be either a breech-loader or a muzzle-loader,—that is to say, some are made to load at the breech; but their construction is such, that if anything in the breech-loading apparatus should go wrong, the gun is not disabled, as with the Armstrong, but can be loaded at the muzzle. The form of the bore can perhaps best be understood by examining the shot of which drawings are given (figs. 5 and 6), and imagining the bore which will fit them. It is in fact in section a hexagon with the angles rounded off. If we imagine this section to move along the bore with a rotation which would make one complete turn while moving along a length of twenty diameters (which is the pitch given in the Illustrated Catalogue of the Exhibition, from which the drawings are taken, for all calibres), it gives the bore. Mr. Whitworth constructs all his guns of homogeneous iron, the smaller calibres being simply bored out of a solid bar, and the larger ones strengthened by wrought-iron hoops forced on by hydraulic pressure. To secure ease in loading, without windage (except to a very small extent), those portions of the sides and angles of the hexagon of the bore on which the shot bears while being rammed down from the muzzle, are eased off slightly. The shot bearing close on the other portions when being driven out by the powder, prevents nearly all waste by windage. The ordinary shot, which is cast, is put into a lathe to be faced to fit the bore, though, on occasion, it may be finished in casting.

Mr. Whitworth has found that, by diminishing off the tail of the projectile, as shown, a greatly increased range is obtained. The shot with which the extraordinary penetrations, lately reported in the newspapers, was obtained against iron plates, is of the form shown in fig. 6, flat-headed. Mr. Whitworth's theory is, that the flat-headed shot punches out a portion of metal clean, while a great deal of the momentum of the pointed shot is lost in compressing the metal sideways, like a wedge, as it penetrates; thereby at each instant creating a greater opposition to its advance. These shot are made of steel or homogeneous iron, or faced with it.

At the late experiments at Shoeburyness, the Whitworth 120-pounder, at a range of 800 yards, sent a flat-headed shell, which, with its bursting charge of 5 lb., weighed 150 lb., through a target consisting of 5-inch iron plates, on a 12-inch teak backing, with a 3-inch wrought-iron skin within, the shell bursting inside. The 70-pounder, at a range of 600 yards, sent a shell weighing, with its bursting charge of 3 lb. 12 oz. of powder, 81 lb., through 42-inch plates, with 18-inch teak backing and a 5-inch skin. No fuze is required for these shells, as the passage through the iron plates heats them sufficiently to ignite the powder. In the ordinary Whitworth shell the percussion arrangement is not required in the fuze, as the flame can communicate with it. In the Whitworth breechloader, the breech is closed by a cap which screws on outside. This cap works in an iron hoop, which is attached by a hinge to the side of the breech. When unscrewed, the cap is by this means opened back like a door, disclosing the bore for the insertion of the shot and cartridge. The vent is in the centre of the cap, in the axis of the gun. The cartridge is contained in a tin or copper case, which prevents any escape of gas. The mouth of the cartridge is closed by a lubricating wad, which lubricates and cleans the bore after each discharge. This wad has also now been adopted with the Armstrong gun, and avoids the necessity of constant sponging out.

These few remarks would scarcely be complete without some comparison between the rival systems. General Morin, in the June number of the Annales du Conservatoire Impérial des Arts et Métiers, makes some remarks which appear

to be just, though there are some portions of the article in which the able author seems to have been labouring under a misconception. He says that the advantages of the Armstrong projectile are compensated for by numerous defects. The manufacture of the projectiles is very delicate. Their nature is such as to reqnire a care in preservation which the hazards of war render it inpossible to afford them. While, on the other hand, after describing the Whitworth system, and commenting on what he considers an excess of nicety and exactness in their manufacture, as shown, which is not by any means indispensable, but may on service be found not only superfluous but inconvenient, -he speaks highly of the Whitworth principle, and says that, when the niceties are modified so far as experience and the

exigencies of service may require, the system is worthy of the highest attention.

War is a rough and rude master, and though we cannot but admire the extraordinary ingenuity and the great mechanical skill brought by Sir W. Armstrong to bear in the construction of his guns, and the perfect contrivance which it is, when we consider the great care required even in preventing corrosion or injury to the bore, we may well doubt, without presumption, whether, though tested in a short campaign in China, from starting on a wrong basis, his ingenuity has not been misdirected, in creating a weapon too delicate for the rough handling and neglect inseparably incident to a protracted European campaign.

Our limits forbid our entering on the description of the numerous other ingenious and original inventions exhibited in the military court; such as Captain Fowkes's admirable collapsing canvas pontoons; Captain Boxer's diaphragm shells and parachute lights; and the various small-arms, &c., which rendered this display so instructive. These will be found described in the jury reports, which we have endeavoured to supplement, to a certain extent, by a popular description of the principles involved.

What will all this lead to? Are armies and navies, like the famed Kilkenny cats, to fight till nothing but their tails are left? Where will it all end? These are complex questions, which must have suggested themselves to many. And yet there is a simple solution which presents itself. In affairs of honour with the small-sword, A's and B's seconds would egregiously fail in their duty if they permitted B to use a rapier an inch longer than A’s. All A's swordsmanship would be thrown away, his most scientific attack lost, if, when finally lunging on his antagonist, B had simply straightened his arm. Before A's rapier could reach him, that one extra inch had given B the victory; he had “ pinked” A.

If an extra length of sword thus secures the victory, one would infer that, in the days when swords were worn and used, they would all have been of the utmost length consistent with the capability of the wearer to wield them. Yet an examination of an old armoury will prove this to have been anything but the case. In the single combat, the chances undoubtedly are, within certain limits, with the longer sword. And yet use and experience seem to have proved that, for all general purposes, a rather under-sized sword was in the long-run most efficient. Is it not so with armies ? For an army with the comparatively short-ranged smooth bore to meet another equipped with the long-range rifle, would in all probability be to court defeat,—a probability varying from certainty on a plain, to even chances on very broken ground. A commander cannot neglect any sudden improvements of his enemy. But when both armies come to improving their arms, and, as a necessary consequence, complicating highly their organization for supply and equipment, will they not, as with the sword, tacitly revert, after experience, to something simpler? The change being, perhaps, hastened, as all history demonstrates, when wars become highly complex, by some man with genius grasping the just medium to which complexity can be carried with efficiency, and, disregarding the long sword of his antagonist, closing with him victoriously. Wars, at all events, have not become more bloody since fire-arms and their improvements have come into vogue.

No. VII.

THE ZOOLOGY OF THE INTERNATIONAL

EXHIBITION.

BY CUTHBERT COLLINGWOOD, M.B., F.L.S., &c.

CATTERED S°

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and down the vast building which has been the centre of attraction to so many thousands during the past summer, the lover of Natural History found ample material to attract his attention, and to encourage him, if he were fortunate to have at his command sufficient time to make a systematic examination of the contents, to devote a day to its zoological and botanical treasures. He would soon perceive, that although there were numberless nooks of the Exhibition which yielded something of interest in this department, nevertheless they were chiefly concentrated about the colonial courts, which in some instances were furnished with scarcely anything else but the animal and vegetable productions of the colony, accompanied by specimens of the raw material derivable from them. This fact at once affords an indication of the manner in which a brief sketch of this department of the Exhibition should be treated; and as the animals and vegetables were thus to a great extent geographically arranged, so also they should be described.

Let us first visit our most distant colonies, which, situated at the antipodes of this country, yield, as might be expected, some of the most remarkable forms of animal life. Victoria, which only emerged into an individual existence in 1851, and is now a flourishing colony of forty-seven municipalities, sent specimens of some of its curious marsupial animals. These creatures, represented by the Kangaroo and Wombat, are characterized

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