A short technical article describing a dyeing method for telling raw (unbleached) cotton from bleached cotton in textiles, including mixtures of the two. Sieber compares it with the Congo-red and wetting-out tests and recommends Victoria Blue B, a basic triphenylmethane dye applied without mordant, which dyes raw cotton deeply and bleached cotton only lightly. He gives a dyeing procedure, explains how the leftover dyebath can be compared by colorimetry to estimate the percentage of each fiber, and describes microscopic examination. Three micrographs show cotton, ramie and flax fibers, raw and bleached.

A paper by Dr. W. Sieber, read at the Twelfth Congress of the International Society of Chemists and Colourists in Carlsbad, on stabilizing diazo printing colours used with beta-naphthol prepares on cotton. He reports that boric acid and tungstic acid can replace acetic acid, gives recipes for preparing the stable diazo colours from p-nitraniline, m-nitraniline or p-nitro-o-anisidine, and compares dissociation constants of the acids. The second half proposes a new explanation of the constitution of diazo compounds, arguing that nitrous acid first forms an addition (molecular) compound with the amine rather than a condensation product.