This textbook has been written for textile students and others who require an introduction to the methods by which the physical and mechanical properties of textile materials and products are measured and investigated. In a very real sense the book has been written by many authors because in preparing the text the writer cast himself in the role of a collector of scattered information. The sources of the information are diverse: lecture notes, standard textbooks, trade journals, manufacturers' instruction books, research journals, and discussion with practicing textile technologists.