Solvents

SOLVENTS SOLVENTS BY THOS. H. DURRANS I Sc LonJ, F. I. C oh rut RFC RCII i MIOR roRiM or . Hi Kt, ROBERTS IO I I l, LONDON BEING VOLUME FOUR OK A SERlEh OF MONOGRAPHS ON APPLIED CHEMISTRY Under the Editorship ot E HOWARD TR1PP, Ih I. F1PTU EDITION RKlISKI AND ENLARGED LO NDO N CHAPMAN HALL LTD. II HENRIETTA STREET, W. C. 2 I9H EDITORIAL PREFACE IN these days of intensive and extensive research, every worker in science or its applications knows how rapidly the contents of text-books and encyclopaedias become out of date and those who wish to see new work published know the difficulties which abnormal taxation and high labour costs offer to the realisation of their desire. The one obvious solution of the problem is the publication of monographs that would focus attention upon recent work, or upon new aspects of old work, and upon their theoretical implications. Such books are usually written by experts lor other experts in related fields of science, or for the well-educated layman whose thirst for new knowledge has not been quenched by the more sepsuous outpourings of the ephemeral press. It is interesting at times to speculate upon what aspects of sur civilisation the future historian will select as the most characteristic of our time. Scientific discoveries and their application to human welfare, we may be sure, will find a place and to these many will add the growth of our sense of values. The value of new work in science varies greatly the golden grain is always accompanied by chaff, and there is no precious ore without country rock. Owing to the difficulty of assessing the value of work at the time of its production, we find that our scientific periodicals stand in clanger of beingswamped by the mass of second-and third-rate material that is thought to be worth publishing, but which posterity will decree would have been better left in manuscript form. It is the first duty of the monograph writer to estimate the value, either actual or potential, of recent work upon the subject of which he writes he must pick out the plums to save others from the indigestion that follows eating the whole pie. Further, in addition to being accurate, his work must be pre sented in a form that is both assimilable and attractive in other words, he must show that lucid exposition can be achieved by the use of few words, if they are rightly chosen, and that attractive presentation is attained rather by clear thinking than by superficial display. The present series of monographs has been designed with these objects and ideals in view. The task which the authors have been set is no easy one so that should performance occasionally fall short of intention, the critical reader is asked to echo the words of Goethe that higher aims, even if unful filled, are in themselves more valuable than lower aims quite attained. E. HOWARD TRIPP. PREFACE TO THE FIRST EDITION BOTH the number of organic solvents which are available to industry and the extent to which they are used have increased greatly during recent years, and there is in conse quence a need for a scientific exposition of the technical application of solvents, more particularly in connection with the cellulose-lacquer industry. A vast mass of valuable information germane to the subject is scattered widely throughout scientific and technical literature, but it is often presented in a profuse manner, lacking cohesion and clarity. The authorhas attempted to bring this information into a concise form wherein the scientific and fundamental aspects of the subject are expressed in a readily comprehensible manner, and to show the relations of these aspects to technical usage. The first part of this book takes the form of a more or less connected series of chapters dealing with the scientific funda mentals in a broad and simple manner...