must be under special " magazine " conditions with regard to precautions against fire or explosion. An " explosive store " is a building, standing apart from others, used for storage of explo- sives which are not kept under magazine conditions. A filled " shell store " is a store in which filled shells are kept.
Although in England the Explosives Act, 1875, expressly exempts Government magazines from its provisions, the condi- tions imposed by the Act apply generally to them.
The general principles that govern the arrangement for a magazine in Great Britain are as follows.
Site. The site should be remote from dwelling houses, and from embankments for preventing inundations, as well as from any prop- erty which might be injured by an explosion. The distances away from buildings in which fires are used vary according to the amount of explosive to be stored, but 200 yd. may be generally assumed to be sufficient. Public thoroughfares or buildings having chimneys should not be permitted in the vicinity of a magazine; and such an extent of land should be acquired round the magazine as would preserve the isolation of the site. In this connexion two points have to be considered : (a) the danger to the magazine arising from too close proximity of other buildings; and (o) the danger to those buildings from the effect of the explosion of the magazine. The best protection is afforded by intervening heights of ground. Failing that, much protection is afforded by massive traverses of earth ; and close plantation of trees will reduce the effects of explosion.
Construction. The structural arrangements must be such that when the magazine is closed it will be as airtight as possible. The building should be substantially built, or excavated in solid rock, earth or mine refuse not liable to ignition ; and be so made and closed as to prevent unauthorized persons having access thereto and to secure it from danger from without. Every magazine should have a lightning conductor. The compartments inside a magazine must be separated by partitions of such substance and character as will effectively prevent explosion or fire in one communicating with another. Protection must be provided against weather and damp- ness, and ventilation cared for. Suitable and uniform temperatures must be maintained. If a heating system is installed, it should be a steam or hot-water apparatus, with the pipes detached from the walls and clear of any timber work. In tropical climates cooling apparatus may be necessary when the temperature is continuously or for long periods above 70 F. In every magazine a chamber or portion of the entrance passage must be set aside for the putting on and taking off of magazine clothing and a barrier arranged between it and the magazine. Metal working parts of every kind used inside a magazine, such as locks, bolts, window fastenings, truck wheels, rails, and working parts of lifting machinery, must be of copper or copper alloy. This applies generally also to hand tools. For floors, a suitable asphalt, devoid of grit, is well adapted, and a rendering of " neat " cement for linings. Dados of glazed brick may be used to prevent the cement being detached by packages knocking against the walls. The interior of the building, and the benches, shelves and fittings should be of non-inflammable material, or be so lined or covered as to prevent the exposure of any iron or steel, or detaching any grit in such manner as to come into contact with the explosives in store. If the magazine be intended for storing cordite only, it should be of as light a form of construction as possible.
Working Conditions. Lighting fires or smoking in or near a mag- azine is, of course, absolutely prohibited. Due provision must be made, by the use of suitable working clothes without pockets, suit- able shoes, searching and otherwise, for preventing the introduction of tobacco pipes, tobacco in any form, matches, grit in any form, exposed iron or steel articles, or any substance or article likely to cause explosion or fire. Operations of weighing and packing should not be carried out in a magazine. Only lamps of special pattern must be used, and these, when not in use, must be kept in the proper lamp room. When electric light is installed, the distributing board must be outside the barrier of the shifting lobby.
For explosive stores the regulations for magazines are modified as regards the necessity for special clothing, but otherwise the regula- tions for magazines should be strictly enforced.
For the purpose of storage, all British service explosives are classi- fied as follows:
GROUP I. including generally all explosives in bulk, and cartridges if not protected by metallic cases. The explosives in this group must be stored in a magazine.
GROUP II. including percussion caps, detonators, fuzes, gaines, igniters, primers, tubes and similar items. The explosives in this group must be kept in an explosive store.
GROUP III. including inert fillings for shells and quick-firing car- tridges. The explosives in this group may be stored in either a magazine or explosive store.
GROUP IV. including various bombs and chemical shell. The explosives in this group must be stored in a separate explosive store.
Each group is subdivided into divisions according to the charac- teristics of the explosives, which must each be kept in a separate compartment of the magazine or explosive store. Packages should be securely stacked in the several bays, and a clear space left between
them and the walls to allow of free circulation of air and to prevent injury from damp.
In fortresses and defensive works, magazines and stores, from their position, must usually be more or less exposed to enemy fire, and must therefore be of sufficiently strong construction to keep out projectiles. Heavy traverses should be built round them. The general regulations regarding safety in magazines must be strictly adhered to, but as regards storage, variations may be permitted so as to allow fuzes and tubes to be kept in the shell stores adjoining the guns, provided that special shelves are fixed for them. In fortresses, cartridges, shells, etc., are always kept in batches according to date of manufacture and filling, in order to obtain uniform effect in firing.
In a theatre of war such definite provision of magazines and explosives stores cannot be made, except perhaps at the main base; and the necessary arrangements have to be improvised at base depdts and advanced dep6ts. Specific instructions cannot be given to meet all the contingencies of varying- local condi- tions, and adequate measures must depend upon local ingenuity and constant supervision. The regulations for safety should be observed, whatever building or shelter is used.
Wooden huts with corrugated iron roofs can be employed in connexion with storage of explosives and ammunition; a height of 8 to 10 ft. from floor to eaves would be suitable, and such huts can be made splinter-proof by layers of sand-bags. A large storage hut may occupy a space 30 ft. wide by 300 ft. long, and would be divided into compartments or bays by traverses made of double walls of galvanized iron sheeting. A floor of road metal, rammed hard, would suffice. When a building is not available, a raised floor with tarpaulin supported on a frame- work, so as to allow of ventilation, is readily inprovised. All explosives should be kept in substantial cases or receptacles where possible. All ammunition necessarily kept in the open should be stored on battens and covered with tarpaulins, which covering should be removed whenever conditions are favourable in order to permit of ventilation and to prevent sweating. When shells are piled in the open they should not be exposed to the direct rays of the sun.
In the World War, ammunition was arranged in the British service as follows
i. boxed ammunition;
ii. unboxed ammunition;
iii. trench-warfare ammunition;
iv. miscellaneous ammunition;
v. demolition explosives.
The stacks of ammunition require suitable disposition to minimize risks of explosion by accident or from enemy fire. For safety, distances of 400 yd. may be taken as adequate between categories, and 30 yd. to looyd. between stacks of the same category. At base clep6ts and advanced dep6ts arrange- ments for storage of ammunition can be made on more or less semi-permanent lines. From these dep6ts, ammunition passes to ammunition parks and ammunition columns where the arrangements have to be improvised as local conditions permit. With mobile warfare the movement of parks and columns would prevent any arrangements for storage, separate from the vehicles, of more than a very temporary character, as the principal object would be to deliver, as rapidly as possible, ammunition from the dep&ts to the particular batteries where it might be most urgently and immediately required.
For trench warfare, the system of " dumps " very naturally came into being, in order that there should be at hand quite a large supply for immediate use, irrespective of the quantity held by an ammunition column. These dumps would be class- ified according to the nature of the ammunition, and might take the form merely of stacks in the open, separated from each other by traverses of sand-bags and lying at convenient places. For dumps in the rearward area, convenience of transport would determine the locality; while for dumps near gun positions, local circumstances would dictate as to whether the dumps might be actually around the gun positions, or placed a few hundred yards away. (F. M. R.)