ike collodion or gun-cotton.
Personally, I have never been able to obtain satisfactory results with
this process in the analysis of nitro-cellulose, and I am of opinion that
the process does not possess any advantage over the nitrometer method, at
any rate for the analysis of gun-cotton.

Table giving the Percentages of Nitrogen and Oxide of Nitrogen in Various
Substances used in or as Explosives:

Name FORMULAE NITROGEN NO_{2}
per cent. per cent.

Nitroglycerine C_{3}H_{5}(ONO_{2})_{3} 18.50 = 60.70
Hexa-nitro-cellulose C_{12}H_{14}O_{4}(ONO_{2})_{6} 14.14 = 46.42
Penta-nitro-cellulose C_{6}H_{8}O_{5}(ONO_{2})_{5} 11.11 = 36.50
Nitro-benzene C_{6}H_{5}NO_{2} 11.38 = 37.39
Di-nitro-benzene C_{6}H_{4}(NO_{2})_{2} 16.67 = 54.77
Tri-nitro-benzene C_{6}H_{3}(NO_{2})_{3} 19.24 = 63.22
Nitro-toluene C_{7}H_{7}NO_{2} 10.21 = 33.49
Nitro-naphthalene C_{10}H_{7}NO_{2} 8.09 = 26.53
Di-nitro-naphthalene C_{10}H_{6}(NO_{2})_{2} 12.84 = 42.12
Nitro-mannite C_{6}H_{7}(NO_{3})_{6} 23.59 = 77.37
Nitro-starch C_{6}H_{8}O_{4}(HNO_{3}) 6.76 = 22.18
Picric acid
(Tri-nitro-phenol) C_{6}H_{2}OH(NO_{2})_{3} 18.34 = 60.15
Chloro-nitro-benzene C_{6}H_{3}Cl(NO_{2})_{2} 13.82 = 45.43
Ammonium nitrate NH_{4}NO_{3} 35.00 =
Sodium nitrate NaNO_{3} 16.47 =
Potassium nitrate KNO_{3} 13.86 =
Nitric acid HNO_{3} 22.22 =
Barium nitrate Ba(NO_{3})_{2} 10.72 =

~Analysis of Celluloid.~--The finely divided celluloid is well stirred, by
means of a platinum wire, with concentrated sulphuric acid in the cup of a
Lunge nitrometer, and when dissolved the nitrogen determined in the
solution in the usual way. To prevent interference from camphor, the
following treatment is suggested by H. Zaunschirm (_Chem. Zeit._, xiv.,
905). Dissolve a weighed quantity of the celluloid in a mixture of ether-
alcohol, mixed with a weighed quantity of washed and ignited asbestos, or
pumice-stone, dry, and disintegrate the mass, and afterwards extract the
camphor with chlor