ON THE MOTHER SUBSTANCES OF WOOD-GUM.
(p. 188) According to the text-books beech-wood may be regarded as the typical raw material for the preparation of the laboratory product known as wood-gum. The author has subjected beech-wood and beech-wood cellulose (Schulze process) to a range of hydrolytic treatments, acid and alkaline, in order to determine the conditions of selective action upon the mother substance of the wood-gum. In the main it appears that this group of furfuroids is equally resistant with the cellulose constituents of the wood; in fact, that the mother substance of wood-gum is a modified cellulose, and exists in the wood in chemical combination with the 'incrusting substances.'
Of the author's experimental results the following may be cited as typical:
| Substance | Yield of furfural p.ct. |
| Original beech-wood | 13.8 |
| After boiling 3 hrs. with 1.25 p.ct. H2SO4 (residue) | 10.1 |
| " " " " 5.0 " " " | 5.6 |
| Cellulose | —isolated by Schulze process (yield 53 p.ct.) | 6.9 |
| " | after further 14 days' digestion with the Schulze acid (HNO3 + KClO3) | 5.9 |
| " | after extraction with 5 p.ct. NaOH in cold (residue) | 5.0 |
| " | after second extraction with 5 p.ct. NaOH in cold (residue) | 4.4 |
UEBER DIE FRAGE NACH DEM URSPRUNG UNGESÄTTIGER VERBINDUNGEN IN DER PFLANZE.
C. F. Cross, E. J. Bevan, and C. Smith (Berl. Ber., 1895, 1940).
ON THE SOURCE OF THE UNSATURATED COMPOUNDS OF THE PLANT.
(p. 179) In distilling for furfural by the usual methods of boiling cellulosic products with condensing acids, the furfural is accompanied by volatile acids, also products of decomposition of the cellulosic complex. A series of distillations was carried out with dilute sulphuric acids of varying concentration from 10-50 H2SO4: 90-50 H2O by weight, using barley straw as a typical cellulosic material. The distillates were collected in successive fractions, and the furfural and volatile acid determined. The results are given in the form of curves. The aggregate yields were as follows:—