No abstract

Six cotton samples were slack-mercerized and stretched to 0.94, 1.0, and 1.036 of the original length. All treatments were given an overtreatment of durable-press resin. The effect on 3.2-mm-gauge bundle tenacity and elongation depended on the amount of stretching. Samples slack-mercerized and stretched to original length increased in tenacity an average of 50%, and with an overtreatment of resin, 89% of the tenacity was retained. Samples differed in their reactions to the treatments. The percent retention of tenacity after treatment varied inversely with the ratio of the 3.2-mm-gauge length tenacity to the zero-gauge length tenacity of the untreated fibers. Clamps and stretchers developed to stretch the mercerized cotton fiber bundles are described. ' . '

The specifications for clamps which can be used to obtain the x-ray angle ~nd tensile measurements of the same specimen of cotton fibers are presented. The tenacity of flat bundles of cotton fibers when these clamps are used is compared with that when Pressley clamps are used. Fiber specimen clamps

Hull Royal Infirmary, Hull HU3 2JZ) writes: The interesting paper on clustering in pityriasis rosea by Dr A G Messenger and others (6 February, p 371) tempts me to recount an anecdote concerning my own family. In July 1961 both my daughters, then aged 11 and 10 years, presented classical pityriasis, the younger following the elder by 10 days. My wife, my son, and I were unaffected. This incident has always suggested strongly to me that the disease is probably of virus origin with low infectivity.. ..

No abstract