Dilute Mineral Acids.

Schulze’s method of isolating cellulose from wood, and from the ligno-celluloses generally, consisted in macerating them for 12 to 14 days with ⁸⁄₁₀ their weight of potassium chlorate dissolved in 12 parts by weight of nitric acid (sp. gr. 1·10), and completing the resolution by afterwards boiling with dilute ammonia. By the action of a more concentrated acid, 50 per cent. HNO₃, at 80° C. (176° F.), a soluble derivative is obtained which has the composition (C₂₅H₄₀NO₂₅). It is a syrupy, highly acid body, dyeing animal fibres a deep yellow shade, and giving with the earthy bases salts of the formula (C₂₅H₃₂NO₂₅M₄), which are precipitated by alcohol from their aqueous solution in the form of bright yellow flocks that dry to a yellow powder.