Digested with caustic soda solution it yielded 33 p.ct. of its weight of the soluble 'acid cellulose.' This product was purified and analysed with the following result: C 43.35 H 6.5. For the direct production of the 'acid' derivative, cellulose was boiled with successive quantities of 30 p.ct. NaOH until _dissolved_. It required eight treatments of one hour's duration. On adding sulphuric acid to the solutions the product was precipitated. Yield 40 p.ct. Analyses: C 43.8 43.8 43.7 H 6.2 6.2 6.3 The cellulose reprecipitated from solution in Schweizer's reagent gave similar analytical results: C 43.9 43.8 44.0 H 6.5 6.3 6.4 _Conversion into nitrates._--The original cellulose, hydral- and acid cellulose were each treated with 10 times their weight of HNO_{3} of 1.48 sp.gr. and heated at 85 deg. until the solution lost its initial viscosity. The products were precipitated by water and purified by solution in acetone from which two fractions were recovered, the one being relatively insoluble in ethyl alcohol. The various nitrates from the several original products proved to be of almost identical composition, C 32.0 H 4.2 N 8.8 with a molecular weight approximately 1350. The conclusion is that these products are all derivatives of a 'hydralcellulose' 6C_{6}H_{10}O_{5}H_{2}O. FORMATION OF FURFURALDEHYDE FROM CELLULOSE, OXYCELLULOSE, AND HYDROCELLULOSE. By LEO VIGNON (Compt. rend., 1898, 126, 1355-1358).