A useful series of experiments, initiated by the Institute, is that noted under (b) and (c) above.
(1) To ascertain the quality of the fibre extracted from the plant at different stages of growth, quantities of 400 lbs. of the stalks were cut at successive stages and the fibre isolated after steeping 14-20 days. The fibre was shipped to England and chemically investigated, with the following results:
| No. | 1. | Cut | before appearance of inflorescence. |
| " | 2. | " | after budding. |
| " | 3. | " | in flower. |
| " | 4. | " | after appearance of seed-pod. |
| " | 5. | " | when fully matured. |
| (1) | (2) | (3) | (4) | (5) | |
| Moisture | 11.55 | 8.74 | 10.7 | 10.0 | 9.72 |
| Ash | 1.1 | 1.1 | 1.1 | 1.1 | 0.90 |
| Alkaline hydrolysis (a) | 6.2 | 8.5 | 9.7 | 8.9 | 7.3 |
| " " (b) | 10.5 | 11.9 | 11.6 | 12.0 | 11.2 |
| Mercerising treatment | 10.2 | 10.7 | 12.0 | 8.1 | 11.0 |
| Nitration | 37.2 | 32.1 | 32.2 | 33.2 | 36.6 |
| Cellulose | 74.0 | 76.2 | 74.1 | 74.8 | 76.4 |
| Acid purification | 0.8 | 0.5 | 0.7 | 2.4 | 1.4 |
It will be thus seen that there are no changes of any essential kind in the chemical composition of the bast fibre throughout the life-history of the plant, confirming the conclusion that the 'incrustation' view of lignification is consistent only with the structural features of the changes, and so far as it has assumed the gradual overlaying of a cellulose fibre with the lignone substance it is not in accordance with the facts.
Examination of the samples from the point of view of textile quality showed a superiority of No. 1 in fineness, softness, and strength; from this stage there is observed a progressive deterioration, but the No. 4 sample (which was taken at the usual period of cutting) is superior to No. 5.
In a further series of experiments (c) the jute was subjected to certain chemical treatments immediately after the separation of the fibre from the plant. These consisted in steeping (1) in solution of sodium carbonate, as well as of plant ashes, and (2) in sulphite of soda, the purpose of the treatments being to modify or arrest the changes which take place in the fibre when press-packed in bales for shipment. The samples were shipped from India under the usual conditions and examined soon after arrival. It was found that the chemical treatments had produced but small changes in chemical composition of the fibre-substance. The sulphite treatment was the more marked in influence, somewhat lowering the cellulose and nitration constants. The conclusion drawn from the results was that they afford no prospect of any useful modification, i.e. improvement of the textile quality of the fibre by any chemical treatments such as could be applied to the fibre on the spot before drying for press-packing and shipment.
The other matters investigated in the Institute laboratory and reported on as indicated above are rather of commercial significance, and contributed no points of moment to the chemistry of cellulose.