Mr T.R.  France claims to have invented some improvements in the manufacture of soluble nitro-cellulose.  His object has been to produce an article as uniform as possible.  His explanation of the imperfect action of the acids is that, however uniform the mixed acids may be in strength and proportions, and however carefully the operations of nitrating, &c., may be conducted, there are variable elements found in different samples of cotton.  The cotton fibre has for its protection a glazed surface.  It is tubular and cellular in structure, and contains a natural semi-fluid substance composed of oil or gum, which varies in nature according to the nature of the soil upon which the cotton is grown.  The tubes of the fibre seem to be open at one end only when the fibre is of normal length.  When, therefore, the cotton is subjected to the action of the mixed acids, the line of least resistance seems to be taken by them, viz., the insides of the tubes constituting the fibre of the cotton, into which they are taken by capillary attraction, and are subject to change as they progress, and to the increased resistance from the oil or gum, &c., in their progress, and therefore to modified action, the result of which is slower and slower action, or chemical change.  He also thinks it is possible that the power of capillary attraction is balanced in the tubes by air contained therein, after a little, sufficiently so to prevent the acids from taking full effect.  To get over this, Mr France uses his cotton in a fine state, almost dust, in fact, and then nitrates in the usual mixture of acids at 40 deg. to 90 deg.  F., the excess of acids being removed by pressure.  He says he does not find it necessary to wash this fine cotton dust in an alkaline solution previous to nitration.  His mixed acids consist of 8 parts HNO_{3} = 42 deg.  B., and 12 parts H_{2}SO_{4} = 66 deg.  B., and he stirs in the dipping tank for fifteen minutes, the temperature being 50 deg.  F. to 100 deg.  F., the temperature preferred being 75 deg.  F.

"Nitrated” Gun-Cotton.—­The nitrates that are or have been mixed with gun-cotton in order to supply oxygen are potassium nitrate, ammonium nitrate, and barium nitrate (tonite).  The total combustion of gun-cotton by potassium nitrate corresponds to the equation:—­

10[C_{24}H_{18}(NO_{3}H)_{11}O_{9}] + 82KNO_{3} = 199CO_{2} + 41K_{2}CO_{3} + 145H_{2}O + 96N_{2},

or 828 grms. of nitrate for 1,143 grms. of gun-cotton, or 42 per cent. nitrate and 58 per cent. gun-cotton.  The explosive made at Faversham by the Cotton Powder Company, and known as tonite No. 1, consists of very nearly half gun-cotton and half barium nitrate.  The relations by weight of total combustion would be 51.6 of gun-cotton to 48.4 of barium nitrate.  The average composition of tonite I have found by analysis to be 51 per cent. gun-cotton to 49 per cent. barium nitrate.  The heat liberated is practically the same as for an equivalent weight of KNO_{3}; but the barium nitrate mixture weighs 2,223 grms. instead of 1,971 grms., or one-eighth more.  The advantage in mixing a nitrate with gun-cotton is that it supplies oxygen, and by converting all the carbon into carbonic acid, prevents the formation of the poisonous gas carbonic oxide (CO).  The nitrates of potassium and barium are also used admixed with nitro-cellulose in several of the sporting smokeless powders.