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an inch thick. These plates are allowed to remain intact for a couple of days, by which time they become as hard as a piece of fine pottery. Very many advantages are gained by this pressure. The density of the powder is increased, which enables it to be conveyed without working into fine dust; its keeping qualities are improved, as it absorbs less moisture than if it were more porous; and lastly, a greater volume of inflammable gas is produced from a given bulk. The pressed cake is now transferred to the maw of one of the most extraordinary machines we have yet witnessed. The granulating house, where the important process of dividing the powder into fine grains takes place, is removed very far away from the other buildings. The danger of the operation carried on within is implied by the strong traverse 15 feet thick at the bottom, which is intended to act as a shield to the workmen in case of an accident. It was here an explosion took place in 1843, by which eight workmen lost their lives-in what manner no one knows, as all the evidence was swept away. To render the recurrence of such lamentable accidents as rare as possible, the machine is made self-acting. At certain times of the day it is supplied with food in the shape of fifteen hundred weight of pressed cake.' This is stuffed into a large hopper or pouch, and the moment the monster is ready the men retire beyond the strong traverse and allow it slowly to masticate its meal, which it does with a deliberation worthy of its ponderosity and strength, emptying its pouch by degrees, and by a triturating process performed by two or three sets of fine rollers, dividing it into different sized grains. These grains it passes through a series of wire sieves, separating the larger ones fitted for cannon powder from the finer kind required for rifles, and depositing them in their appropriate boxes, which, when full, it removes from its own dangerous proximity, and takes up empty ones in their place. All the larger undigested pieces it returns again, like a ruminating animal, to its masticating process until its supply is exhausted. Then, and not till then, like Mademoiselle Jack, the famous elephant, it rings a bell for some fresh cake.' The workmen allow it about five minutes' grace to thoroughly assimilate the supply already in its maw, when the machine stops, and they enter with another meal. The floors of all the different houses are covered with leather neatly fastened down with copper nails, and the brush is never out of the hands of the workman: even while you are talking to him, he sweeps away in the gravest manner in order to remove any particles of powder or grit that may be on the floor; this he does mechanically, when not a particle of anything
is to be seen, just as a sailor in a crack ship always holystones the deck, clean or dirty, the moment he has any spare time.
The powder thus separated into grains is still damp and full of dust. To get rid of this it is taken by water to the dusting house, where it is bolted in a reel like so much flour. It has now to be glazed, a very important operation, performed by placing it in large barrels, which revolve with their load thirtytwo times a minute for three hours together. By the mere friction of the grains against each other, and the sides of the barrel, a fine polish is imparted to the surface of the grain, which enables it to withstand the action of the atmosphere much better than when it is left unglazed. It is now stoved for 16 hours in a drying-room heated by steam pipes to a heat of 130 degrees Fahrenheit, and is then finally dusted and proved. There are many methods of proving, but the simplest and most efficacious is to fire the powder from the weapon it is intended to serve. Thus cannon powder is proved by firing a 68-pound solid shot with a charge of 2 ounces of powder -- a charge which should give a range of from 270 to 300 feet. If the powder passes the test, which it generally does, it is packed in barrels holding 100 lbs. each, marked L. G. (Large Grain), and F. G. (Fine Grain), as the case may be, and carried to the provisional magazine. When 500 barrels have accumulated they are despatched in a barge to the Government magazine at Purfleet, near the mouth of the Thames, the Lea forming the connecting link of water between the canals of the works and that river.
The produce of this establishment, which had fallen so low as 4500 barrels per annum in 1843, is now so increased by improved machinery that 20,000 barrels a-year can be manufactured, and of the very best quality. Even this supply is far below the consumption during a time of war, and contractors have, and always will have, to furnish a portion of the required supplies ; but it seems that a model mill is useful for the double purpose of keeping up a due standard of quality,* and of keeping down price. On the uniform strength of the powder depends the accuracy of artillery fire: hence the necessity of having some known standard of quality from which contractors should not be allowed to depart. The improvements which have taken place in the manufacture are very marked. About the year 1790, when powder was supplied to Government wholly by contract, the regulation weight of charge for a cannon was half the weight of
* The merchants are provided annually with a sample of Waltham Abbey powder to guide them in their manufacture.
the ball ; it is now less than one-third : therefore two barrels are now used instead of three, a reduction of bulk which economises stowage on board ship as well as in the field. Formerly powder had a range of 190 feet only; the range is now increased to 268 feet! This vast improvement is simply the consequence of the care with which the powder is worked, and the attention bestowed on every detail of the mills since their direction fell into the hands of Colonel Tulloh, Colonel Dickson, and Colonel Askwith, the present Superintendant.
There is a department at the Woolwich Arsenal to which we must now return, of which the establishments at Enfield and Waltham Abbey may be considered but outlying offshoots. Beyond the canal, at the extreme end of the ground, lie the establishments devoted to the more dangerous portions of pyrotechnic manufacture, such as the filling of rockets, of friction tubes, the driving of fuses, &c. These ticklish operations used
, to be conducted in ill built sheds in the laboratory square, where a sad explosion took place during the war, and Captain Boxer, determining to reduce the risk of accidents, transferred the whole of them in 1854 to this open space, far away from the neighbourhood of fire. The sixteen houses used for fuse driving and friction-tube making are isolated from each other much in the same manner as the incorporating mills at Waltham Abbey: we need not therefore describe them. The rocket manufactory is also so carefully arranged that accidents can rarely happen. The method of driving the composition into these frightfully destructive implements of war was, until lately, not only barbarous but dangerous in the extreme, being forced in by a * monkey,' or small pile-driver, worked by eight men. The pressure of water now does the work silently, effectually, and safely. The rocket is so fixed while it is being filled, that in case of an accident the discharge will fly through the roof; grit and iron are as carefully excluded as in the powder mills ; open spaces around the buildings are covered with turf and planted with shrubs, and a raised causeway of wood keeps the communications between the different magazines free from all substances likely to produce friction. The visitor may no more enter one of these carefully guarded buildings with his shoes on than he could walk into the mosque of St. Sophia, at Constantinople, similarly shod. With equal care the process of greasing the bullet end of the small-arm cartridges is carried on in this portion of the Arsenal. For a long time no lubricating material could be found that reinained unaffected in all climates—a very important desideratum, considering the manner in which our stores of war are moved about from the depths of arctic waters
to the burning summers of the torrid zone. Captain Boxer, however, in a happy moment, thought of the little busy insect that builds a store-house warranted to keep in all temperatures, and adopted bees' wax, which, added to a little fat, makes a compound which answers the purpose perfectly. The cartridges are dipped about an inch deep into a receptacle of this liquid kept fluid by the heat of gas. As we watched the process going on we could not avoid reflecting from what insignificant causes great events arise, and that a rebellion which well nigh snatched India from our grasp sprung from this very cauldron seething with "hell-broth thick and slab.'
The different departments of the Royal Arsenal are separated by large open spaces, in which the rougher materials of war are deposited. The roadways, laid with iron trams, which greatly facilitate the transfer of heavy guns, are lined here and there with pyramids of shot and shell, lackered and shining in the sun. These missiles are continually circulating along the shoots from one spot in the Arsenal to another, passing at one time under foot, at another overhead, the action of gravity being pressed into the service with other labour-saving contrivances, to remove 13-inch shells and 98-pounder solid shot, sometimes to very considerable distances. Vast as are the stores of these warlike implements—and far as the vistas of pyramids stretch (and there are no less than 688,000 in the Arsenal at present), they would speedily be drained by a short return of war, in which artillery now plays so prominent a part. At the siege of Sevastopol alone, which scarcely occupied eighteen months, no less than 253,042 shot and shell of all sizes were fired from our batteries, a number which the enemy surpassed, in one attack alone, if we are to believe the evidence afforded by some of the ravines, in which this iron rain descended so thickly that it paved the ground, and prevented the grass from springing up. The French were even more prodigal of these projectiles ; for, according to the report made to the Emperor, 1,100,000 of them were sent by our allies into the doomed city.
The neighbourhood of each department is generally indicated by the class of war stores to be seen at hand. We may
be sure we are near the great-gun foundry, for instance, when we see the long files of iron guns of all sizes and patterns, from the light 32-pounders to the truly formidable 98-pounders of the naval service, flanking the road, compared with which the light brass field-pieces that fringe the wall of the building itself seem the merest toy-guns. Here and there trim grass-plats are seen with a neat edging of three hundred 13-inch mortars, and at the grand entrance of the foundry itself enormous shells, a yard in diameter, prepared for
Mallett's mammoth mortar, are planted as if to show how daring are the ideas of modern war, which proposes to throw such Titanic missiles at the enemy. Here too may be seen veterans which have seen service-avenues of wounded guns from the Crimea. These are the picked specimens of the 88 pieces of ordnance either disabled by the enemy or worn out by their own fire in that ever-memorable siege. One, a 68-pounder, was shattered by a singular accident; just as it was being discharged a shell fired by the enemy exploded in its mouth, and destroyed it after it had fired no less than 2000 rounds. Another gun, which is split in the muzzle, was hit thirteen times. There appears to have been luck in this mystic number, however, for by the aid of an iron band the mishap was repaired, and it went on doing duty until one of its trunnions was knocked off, and even then, like the gallant Widderington, at Chevy Chase, it fought upon its stumps; for, on being sunk into the ground, and fired at a high elevation, it was kept at work up to the end of the siege. Some of these guns are pitted with cannonshot even as far back as the breech, and one or two are hit in their very sternmost parts. These wounds are the result of ricochet firing, a kind of practice which enables a shot to drop in the most unexpected places.
In the mounting yard, as it is termed, which lies between the gun and carriage factories, the field pieces are mounted upon their carriages and fitted up for service previous to their removal to the depôt of artillery near the Common. Since the war the captured cannon from Sevastopol have been stored here preparatory to their being either broken up or distributed as trophies to the various towns of the United Kingdom. Of these guns 1079 are of iron and 94 of brass. They are of admirable metal, and would have proved very serviceable, except that unfortunately their bore does not suit any of our shot. Gun carriages rent by the bursting of guns, or so unscientifically constructed as inevitably to destroy themselves, like the iron carriages taken from the enemy at Kertch, are kept as lessons for the Captain Instructor to dwell upon, when he takes round his bevy of young artillery cadets. This official performs the essential duty of giving the future artillery officer a clear insight into the method of constructing and repairing all the more essential engines and tools he will have to work with--such as guns, guncarriages, &c., and of obtaining a general notion of the relative strength of metals, and of the value of the various materials out of which the munitions of war are formed. The vast workshops of Woolwich afford an admirable field for the acquisition of this kind of knowledge.