Crum, Walter

(b. Glasgow, Scotland, 1796; d. Rouken, Scotland, 5 May 1867)

chemistry.

For a period of forty years Walter Crum devoted himself to the improvement of calico printing by the application of chemical knowledge. He attended the University of Glasgow and was a student of Thomas Thomson’s from 1818 to 1819. Crum utilized his knowledge of chemical analysis in his father’s calicoprinting business. His analytical interests extended into pure research, and his fourteen published papers, although on subjects connects with calico printing and dyeing, have a value beyond their applicability to this chemical art. Crum became a fellow of the Royal Society in 1844 and was one of the original members of the Chemical Society of London. He joined the Royal Philosophical Society of Glasgow in 1834 and was its president from 1852. Crum also played a leading role in the public life of Glasgow and was president of Anderson’s College, founded in 1796 for the instruction of artisans and others unable to attend the University of Glasgow.

Crum’s scientific contributions reveal considerable talent and originality. His very first paper (1823) established his European reputation. Crum undertook an analysis of indigo, preparing pure indigo by sublimation and determining its composition in a remarkably accurate piece of organic research even though organic analysis was still imperfect and difficult. Chemists accepted his formula for indigo. He also investigated the sulforic acids of indigo, obtaining two new derivatives by the action of sulfonic acid.

Crum made several valuable contributions to analytical chemistry. He discovered the lead dioxide test for manganese. In 1847 he developed an ingenious method for the analysis of nitrates, converting them into nitric oxide by the action of sulfuric acid and mercury. He then applied this method to the determination of the amount of nitrogen in guncotton. Among his other contributions was the first preparation of copper peroxide and of colloidal alumina.

In 1844 Crum proposed a theory of dyeing that involved both a mechanical and a chemical aspect. The dyer applied to cotton the mineral basis for the color in a solution of a volatile acid. On drying, the acid volatilized, leaving the metal oxide to adhere to the fiber. This adherence, Crum asserted, was a mechanical action only and was confined to the interior of the tubular structure of the fiber. On dyeing the cotton there was now a purely chemical attraction between the metal oxide inside the cloth and the organic dye, producing a fixed colored compound in the cloth. Crum claimed that his theory resembled the older mechanical theory of dyeing held by Macquer and others more than it did the newer, purely chemical theory held by Berthollet and most contemporary chemists.

In an earlier work (1830) Crum wrote on colors and presented a color theory resembling Goethe’s in that the prismatic colors were produced, contrary to Newton, not from white light but from blackness. Crum had made prismatic experiments since 1822 and concluded that white light did not contain any colors and that black was the source of the three primary colors—red, yellow, and blue—as proved, said Crum, by his experiments in which the recomposition of light from these colors produced black, not white.

BIBLIOGRAPHY

I. Orginal Works. Crum’s analysis of indigo is in “Experiments and Observations on Indigo and on Certain Substances Which Are Produced by Means of Sulphuric Acid,” in Annals of Philosophy, 5 (1823), 81–100. His analysis of guncotton is in “On a Method for the Analysis of Bodies Containing Nitric Acid, and Its Application to Guncotton,” in Philosophical Magazine, 30 (1847, 426–431, The theory of dyeing is in “On the Manner in Which Cotton Unites with Colouring Matter,” ibid., 24 (1844), 241–246. Crum’s color theory is found in An Experimental Enquiry Into the Number and Properties of the Primary Colours and the Source of Colour in the Prism (Glasgow, 1830); there is a French translation by Achille Penot in Bulletin de la Société industrielle de Mulhouse, 4 (1831), 544–593. All of his papers are listed in the Royal Society’s Catalogue of Scientific Papers, II, 101.

II. Secondary Literature. There are brief obituary notices on Crum in Proceedings of the Royal Society, 16 (1867–1868), viii-x and Journal of the Chemical Society, 21 (1868), xvii-xviii.

Albert B. Costa