t requires to be determined is
the percentage of water that it contains. It is best done by weighing out
about 1,000 grms. upon a paper tray, which has been previously dried in
the oven at 100 deg. C. for some time, and become constant in weight. The
trayful of cotton is then placed in a water oven, kept at 100 deg. C., and
dried as long as it loses water. The loss gives the percentage of water.
It varies from 20 to 30 per cent. as a rule in "wet" cotton.

OUTLINE SCHEME FOR THE ANALYSIS OF NITRO-EXPLOSIVES
_______________________________________________________________________
| |
| Exhaust dried substance with Anhydrous Ether in Soxhlet's Fat |
| Extraction Apparatus. |
|_______________________________________________________________________|
| |
| _Solution_--Divide into two parts ~A.~ and ~B.~ |
|_______________________________________________________________________|
| |
| ~A.~ |
| |
| Allow ether to evaporate spontaneously. Dry residue in vacuo over |
| H_{2}SO_{4} and weigh. Equals nitro-glycerine, resin, camphor, and |
| paraffin. |
| |
| The nitro-glycerine in this residue may be decomposed by heating |
| with a solution of alcoholic potash. Water may then be added, and the |
| alcohol evaporated off on the water bath. From this solution the |
| resin may be precipitated by HCl, filtered off, dried, and weighed. |
| Solution containing the paraffin is treated with AmS solution and |
| heated. On cooling the paraffin separates, and may be separated. |
| Residue may be shaken with CS_{2} to remove camphor. |
|_______________________________________________________________________|
| |
| ~B.~ |
| |
| Add phenol-phthalein and ti