The process of manufacture of this powder is briefly as follows:—­

Wood of clean growth is treated by the well-known sulphite process for producing pure woody fibre, which is very carefully purified, and this, after drying, is steeped in a mixture of nitric and sulphuric acids, to render it a nitro-compound and the explosive base of the powder.  This nitro compound is carefully purified until it stands the very high purity requirements of the Home Office, and is then ground with oxygen-bearing salts, &c., and the whole is formed into little irregular-shaped grains of the desired size, which grains are dried and hardened by steeping in a suitable solvent for the nitro compound, and after finally drying, sifting, &c., the powder is stored in magazines for several months before it is issued.  When issued, a very large blend is made of many tons weight, which ensures absolute uniformity in the material.

There is in England a standard load adopted by every one for testing a sporting powder; this charge is 42 grains of powder and 1-1/8 oz.  No. 6 shot—­this shot fired from a 12-bore gun, patterns being taken at 40 yards, the velocity at any required distance.

The standard muzzle velocity of Schultze gunpowder is 1,220 feet per second.

The mean 40 yards ditto is 875 feet per second.

The mean 20 yards ditto is 1,050 feet per second.

The internal pressure not to exceed 3.5 tons.

This Company also manufactures a new form of powder, known as Imperial Schultze.  It is a powder somewhat lighter in gravity; 33 grains occupies the bulk charge, as compared with the 42 grains of the old.  It follows in its composition much the lines of the older powder, but it is quite free from smoke, and leaves no residue whatever.

The E.G.  Powder.—­This is one of the oldest of the nitro powders.  It was invented by Reid and Johnson in 1882.  It is now manufactured by the E.G.  Powder Company Limited, at their factory near Dartford, Kent, and in America by the Anglo-American E.G.  Powder Company, at New Jersey.  The basis of this powder is a fine form of cellulose, derived from cotton, carefully purified, and freed from all foreign substances, and carefully nitrated.  Its manufacture is somewhat as follows:—­Pure nitro-cotton, in the form of a fine powder, is rotated in a drum, sprinkled with water, and the drum rotated until the nitro-cotton has taken the form of grains.  The grains are then dried and moistened with ether-alcohol, whereby the moisture is gelatinised, and afterwards coloured with aurine, which gives them an orange colour.  They are then dried and put through a sieve, in order to separate the grains which may have stuck together during the gelatinising process.