[To the Editor of the SPECTATOR.] Sin,—In the article " Shall the Silk Worm Die ?" in your issue of April 24th by Mr. F. Yeats-Brown, reference was made to the discovery of mercerizing by Mercer. As this is an error it should be corrected ; Mercer was not the discoverer of mer- cerizing. What he did discover was that by treating cotton with strong caustic soda it shrank in length, thickened, became stronger and also had an increased affinity for dyes. No reference was made to the lustre nor was any lust* produced. .
What is now known as mercerization was discovered by an English chemist called Lowe, who found that by mechanic- ally, preventing the shrinkage of the cotton when treated with 'Strong caustic soda an internal stress was' produced in the fibre. which changed it physically from a twisted yarn to more or less of a tube, similar to silk, thus producing a lustre.
The Lancashire manufacturers failed to appreciate the discovery. of Lowe and it was dropped, but at a later date was recliseatiered by Tomas and Prevost of Crefeld, who having dyed some yarn in a wrong shade had occasion to find a means to destroy the colour so that the yarn could be redyed. They found that strong caustic soda was the only thing available but it shrank the yarn considerably. So -in order to prevent the shrinkage they put the yarn on a worsted dyeing machine, thus preventing the shrinkage, and in this way rediscovered what Lowe had hawked about Lancashire without avail.— I am,. Sir, &c.,