Notices respecting New Books. 287 
The last chapter of the book is on the distribution of radio- 
activity in air, earth, and water. It closes like an unfinished 
drama of absorbing interest. We know that none of us will live 
to see the finished work, but we close the book feeling that it is 
well to have seen so much in our day. J.J. 
May 20th. 
Mathematical and Physical Papers. By the late Sir GEORGE 
GAsEieL STOKES, Bart., Sc.D., LLOD., D.C.L., Past: Pres. BS., 
§c. Vol. IV. Cambridge: at the University Press. 1904. 
Pp. viii+ 378. 
A MELANCHOLY interest attaches to the publication of the fourth 
volume of Sir George Gabriel Stokes’s Papers, for its appearance 
reminds one of the concluding words contained in the preface to 
vol. i1.,in which the author expressed the hope that, ‘should 
life and health last,” he would be able to put the remainder of 
his papers together without delay. Unfortunately, “these con- 
ditions”—as Dr. Larmor, who edits the present volume, remarks 
in his preface— were not destined to be fulfilled ; and the task 
of completing this memorial of his genius has fallen to other 
hands.” 
In vol. iti. was commenced the series of important memoirs 
which contain Sir G. G. Stokes’s contributions to optical theory ; 
and this series is continued in the present volume, of which they 
form the bulk. The period covered is 1852-1876. There were, 
however, numerous other subjects which claimed the author’s 
attention, and we find notes on the theory of the Electric Tele- 
graph, on Airy’s Harton Pit experiment, on Clark’s investigation 
regarding the change of form assumed by wrought iron and other 
metals when heated and then cooled by partial immersion in 
water: aud many others. An appendix contains some most 
interesting correspondence between Sir G. G. Stokes and Lord 
Kelvin on the nature and possibilities of spectrum analysis. 
The present volume, which is adorned with a beautifully executed 
portrait taken from an oil painting made in 1874 by Mr. Lowes 
Dickinson, is not the concluding one of the series. And the 
remaining papers are promised in a fifth volume, which is to 
contain a biographical notice, and possibly also a selection from 
Sir G. G. Stokes’s scientific correspondence. 
Die Kathodenstrahlen. Von G. C. Scumipt, a. 0. Professor der 
Physik an der Universitit Erlangen (“Die Wissenschaft,” 
Heft 2). Braunschweig: F. Vieweg und Sohn. 1904. Pp. 
vi+120. 
Since the appearance of the electron theory, the interest taken by 
the scientific public in the phenomena exhibited by the discharge 
of electricity through gases has been enormously quickened. There 
