fumes |
| | | | | | after |
| From 'A' sample. | 50 | 50 | 187.5 | 55 | 100 |
| | 60 | 40 | 187 | 45 | 100 |
| | 70 | 30 | 185 | 45 | 100 |
| | 80 | 20 | | 50 | 100 |
| __| 92 | 8 | 185 | 50 | 100 |
| | Structure- | | | | |
| | less powder. | | | | |
| " 'B' sample __| 50 | 50 | 183 | 35 | 100 |
| " 'C' sample | Ordinary service | 185 | 10 | 41 |
| | guncotton | | | |
|___________________|______________|_________|_____________|_______|_______|

a certain solvent action, and on adding an equal bulk of water, the
dissolved nitrate for the most part is precipitated, at the same time
that the undissolved but disintegrated and swollen product undergoes
further changes in the direction of increase of hardness and density.
The product being now collected on a filter, freed from acetone by
washing with water and dried, is a hard and dense powder the fineness of
which varies according to the attendant conditions of treatment. With
the main product in certain cases there is found associated a small
proportion of nitrate retaining a fibrous character, which may be
separated by means of a fine sieve. On examining such a residue, we
found it to contain only 5.6 p.ct. N, and as it was insoluble in strong
acetone, it may be regarded as a low nitrate or a mixture of such with
unaltered cellulose. Confirming this we found that the product passing
through the sieve showed an increase of nitrogen to 13.43 p.ct. from the
13.31 p.ct. in the original. Tested by the heat test (50 minutes) and
stability test (no fumes after 100 minutes), we found the products to
have the characteristics previously noticed.

It is clear, therefore, that this specifically regulated action of
acetone produces the effects (a) of disintegration, and (b)
stabilisation. It remains to determine whether the latter effect was
due, as might be supposed, to the actual elimination of a compound or
group of compounds present in the original nitrate, and to be regarded
as the effective cause of insta