392 Scientific Intelligence. 



replaced by copper bars and mercury contacts of specially low 

 resistance. The thermometers employed were of about 10 ohms 

 resistance, and were provided with the compensating leads, 

 devised by Mr. Callendar. The maximum current which can be 

 used in accurate measurements with these thermometers is about 

 0'02 ampere, and therefore the galvanometer employed required 

 to be extremely sensitive. The instrument selected was a low 

 resistance astatic one with vertical needle system of the type 

 described by Weiss, and gives at the greatest sensibility at which 

 the zero is steady one scale division for 1 XlO~*<^ ampere at 2500 

 scale divisions distance. 



With this arrangement the influence of various conditions on 

 the final temperature attained by the mixture of ice and water 

 was studied. The results were found to be in close agreement 

 with the theoretical deductions of Nernst, and it was found that 

 with the right conditions, it was quite easy to keep the tempera- 

 ture in the freezing vessel constant, to within one or two ten- 

 thousandths of a degree for an hour at a time. 



The conclusion drawn from the previous experiments made with 

 mercurial thermometers as to the small influence of changes in the 

 external temperature, and in the temperature of the circulating 

 liquid on that of the freezing vessel, was also confirmed, and it 

 was found that in the final form of apparatus adopted, a change 

 of two or three degrees in the temperature of the circulating 

 liquid only caused the temperature of the mixture in the tube to 

 alter by three or four ten-thousandths. 



13. Roentgeri Hays and Phenomena of the Anode and Cathode ; 

 principles^ applications and theories^ by Edward P. Thompson. 

 Concluding chapter by Prof. William A. Anthony. 190 pp. 

 8vo. New York (D. Van Nostrand Company). — This volume 

 contains a series of brief abstracts of the results and methods of 

 many experimenters on the phenomena of the electric discharge, 

 beginning with Faraday (1831) but including particularly the 

 work of the past year upon the so-called X-rays of Rontgen. 

 These notes are in numbered paragraphs arranged somewhat 

 according to special subject under a series of chapters, with fre- 

 quent cross references designed to call attention to the relation 

 between them. Numerous illustrations are introduced including 

 some forty-five half-tone reproductions of "sciagraphs" obtained 

 by difi*erent experimenters. The general public will find this an 

 interesting and convenient digest of the literature of the Rontgen 

 rays. 



14. The Journal of Physical Chemistry. Edited by Wilder 

 D. Bancroft and Joseph E. Trevor. Vol. I, No. 1. 68 pp. 

 Published at Cornell University, Ithaca, N. Y. October, 1896. 

 — This new Journal comes forward to take a place not hitherto 

 occupied among the scientific periodicals of the country. It will 

 doubtless receive cordial support from all those interested in the 

 department it represents. The first number contains articles by 

 A. E. Taylor on irreversible cells (pp. 1-20) ; by F. Wald on 



