Amberite is a nitro-cellulose powder of the 42-grain type of sporting gunpowders, and is manufactured by Messrs Curtis’s & Harvey Limited, at their Smokeless Powder Factory, Tonbridge, Kent.  It consists of a mixture of nitro-cellulose, paraffin, barium, nitrate, and some other ingredients.  It is claimed for this powder that it combines hard shooting with safety, great penetration, and moderate strain on the gun.  It is hard and tough in grain, and may be loaded like black powder, and subjected to hard friction without breaking into powder, that it is smokeless, and leaves no residue in the gun.  The charge for 12 bores is 42 grains by weight, and 1-1/8 oz. or 1-1/16 oz. shot.  The powders known as cannonite[A] and ruby powder, also manufactured by Messrs Curtis’s & Harvey Limited, are analogous products having the same general characteristics.

[Footnote A:  For further details of cannonite, see First Edition, p. 181.]

Smokeless Diamond, also manufactured by the above mentioned firm, is a nitro-cellulose powder of the 33-grain type of sporting gunpowders.  It was invented by Mr H.M.  Chapman.  The manufacture of Smokeless Diamond, as carried out at Tonbridge, is shortly as follows:—­The gun-cotton, which is the chief ingredient of this powder, is first stoved, then mixed with certain compounds which act as moderators, and after the solvents are added, is worked up into a homogeneous plastic condition.  It then undergoes the processes of granulation, sifting, dusting, drying, and glazing.  In order to ensure uniformity several batches are blended together, and stored for some time before being issued for use.

It is claimed for this powder that it is quick of ignition, the quickness being probably due to the peculiar structure of the grains which, when looked at under the microscope, have the appearance of coke.  The charge for a 12 bore is 33 grains and 1-1/16 oz. shot, which gives a velocity of 1,050 feet per second, and a pressure of 3 tons per square inch.

Greiner’s Powder consists of nitro-cellulose, nitro-benzol, graphite, and lampblack.

B.N.  Powder.—­This powder is of a light grey or drab colour, perfectly opaque, and rough to the touch.  It consists of a mixture, nitro-cellulose and the nitrates of barium and potassium.  Its composition is as follows:—­

Insoluble nitro-cellulose 29.13 parts
Soluble nitro-cellulose 41.31 "
Barium nitrate 19.00 "
Potassium nitrate 7.97 "
Sodium carbonate 2.03 "
Volatile matter 1.43 "

This powder is a modification of the Poudre B., or Vieille’s powder invented for use in the Lebel rifle, and which consisted of a mixture of the nitro-celluloses with paraffin.

Von Foster’s Powder contains nothing but pure gelatinised nitro-cellulose, together with a small quantity of carbonate of lime.

The German Troisdorf Powder is a mixture of gelatinised nitro-cellulose, with or without nitrates.