BIBLIOGRAPHY OF X-RAY LITERATURE AND RESEARCH. 189697, FRONTISPIECE.- Copyright. BIBLIOGRAPHY OF X-RAY LITERATURE AND RESEARCH, 1896-1897. BEING A READY REFERENCE INDEX TO THE LITERATURE ON THE SUBJECT OF RONTGEN OR X-RAYS. EDITED BY CHARLES E. S. PHILLIPS, II With an HISTORICAL RETROSPECT AND A CHAPTER, PRACTICAL BY THE EDITOR. - PREFACE. IT is hoped that there will be found in this compilation something more than a mere glorified book catalogue or miscellaneous reference list. Rather, indeed, is it a humble attempt to place in the hands of the experimentalist a useful key to the literature of X-Rays, and to weave into the dry matter of fact a thread of interest. It may not appear necessary perhaps, to supplement so definite a title as Bibliography with any further explanatory remarks here nor would I add more now were it not that I wish to draw attention to one or two matters which have presented themselves during the progress of the work. To begin with, besides the reference numbers and cross-references themselves all useful enough, it is hoped there are cases where it was thought advisable to couple together the references relating to similar matters. Then again, brief abstracts have been given as a further guide to the nature of the articles to which they relate, and all have been condensed as much as was reasonably possible. Further than this, an occasional subject-heading has been slightly altered where that was thought to be an advantage. . The references relate to the principle articles which have appeared on the subject of X-rays up to March, 1897, but it is intended to re-arrange time and bring it quite up to date. the Book from time to I cannot hope to have done more than reduce errors to a minimum. If any still remain, I shall indeed be obliged to readers who will be good enough to bring them to my notice. May I further add that it would be considered a great privilege if authors of important Papers or Books upon Rontgcn Rays and allied subjects, will, from time to time, call my attention to their work in order that the Biblio- graphy may always be made as complete as possible. The study of electric discharges has been carried on now over a considerable period. Very many physicists have added their quota of ideas or experimental results to the until it has already existing heaps of unsorted knowledge, become not only useful, but as most think, absolutely necessary for further progress that some real attempt be made to separate the wheat from the chaff, to sort out the mere paper of it all, and condense the ideas and results. In conclusion, I desire to acknowledgemy indebtedness to those who have kindly assisted, either by useful suggestions or in checking the cross-references while to my assistant, Mr. Coton, and to Mr. George Tucker, the publisher, my especial thanks are due for the interest they have shown and for the help they have given. CHARLES E. S. PHILLIPS. HISTORY RETROSPECT. HISTORICAL, has toiled hard to record the small beginnings out of which there has sprung one of the most important branches of physical science. Notwithstanding this, however, a vagueness still clings to the early accounts of a certain so-called electric egg, and of the peculiar properties observed concerning it all doubtless associated then by many with witchcraft or devil-doings, and now by no means to be laid aside as useless, but rather utilised as a starting point. To Otto von Guericke we owe the very first vacuum g5Q experiment. His work laid the seed very potential as GUERICKE. we now know which has given such an abundant harvest...