The textile fibres form the raw materials for many of our greatest industries, and hence it is of importance that the facts concerning them Should be systematized into some form of scientific knowledge. The author has attempted, however, not to allow the purely scientific phase of the subject to overbalance the practical bearing of such knowledge on the every-day problems of industry. Heretofore, the literature on the textile fibres has been chieﬂy confined to a chapter or two in general treatises on dyeing or other textile subjects, or to specialized books such as Hohnel's work on the microscopy of the fibres. It has been the author's endeavor, in the present volume, to bring together, as far as possible, all of the material available for the study of the textile fibres. Such material is as yet incomplete, and rather poorly organized at its best; but it is hoped that this volume may prove a stimulus along the several lines of research which are available in this field. Unfortunately, the subject of the textile fibres has been lamentably neglected by chemists, although there is abundant indication that a fertile field of research is open to chemists in this direction, and such work would have not only a scientific value, but might also lead to great industrial worth.