Use of the Polarizing Microscope in Cotton Classing

Abstract

For some eighteen months the Pequot Mills, manufacturers of Pequot sheets and pillow cases, Salem, Mass., have been using the polarizing, microscope in their cotton classing for positive identification of the presence or absence of immature fibre. The same microscope, with the addition of a disc-micrometer for the eyepiece, is used to measure the ribbon-width or fineness of fibres. The purpose, results and technique are described by C. L. Pattee, Pequot Mills technician, in the October number of Textile World, and the article is reprinted here in large part. While admitting that this adaptation of scientific research is not perfect, the author states that it is a valuable aid to the cotton classer and buyer in evaluating the character of cotton. For suggestions leading to this practical application of the polarizing microscope the author gives credit to E. R. Schwarz, associate professor of textile engineering, Massachusetts Institute of Technology, and also prominently identified with U. S. Institute for Textile Research, Inc.