PREFACE TO THE FOURTH EDITION.
In the present edition of this work a few new subjects have been added and the text has been somewhat altered in order that certain recent advances and changes might be noted and brought into daily service. I have not been unmindful, however, of the fact that to be of the greatest possible use to our profession this volume must remain small and compact.
I hear frequently that this Handbook is valued by my fellow-workers and that it is to many of them a daily help and companion. This is a source of great pleasure to me, and I hope that this new edition will be found more useful even than any of its predecessors.
A. K. Beck, R. N.
Chicago, Ill.,
March, 1919.