264 Scientific Intelligence. 



ration of subsequent volumes are Americans, so that the work 

 will have an international character. The complete work will 

 consist of eight volumes, which will be issued rapidly, h. l. w. 



4. Introduction to Physical Chemistry ; by Harry C. Jones. 

 12mo, pp. xv + 279. New York, 1910 (The Macmillan Co.).— 

 This book is practically an abbreviated edition of the author's 

 Introduction to Physical Chemistry and is designed for a shorter 

 college course in physical chemistry. Much of the text and many 

 figures are taken from the larger book. The six chapters in the 

 book are on the atom, gases, liquids and solids, solutions, thermo- 

 chemistry and photochemistry, electrochemistry, and chemical 

 dynamics and equilibrium. 



It will probabty find considerable use in the colleges. 



h. w. F. 



5. Change from Positive Reflection to Negative through Pres- 

 sure. — O. Lummer and K. Sorge have repeated Lord Rayleigh's 

 observations on this subject, moved, probably, to a consideration 

 of the subject by the remark of Rayleigh, that in the study of 

 surface conditions by means- of light much can be learned of 

 the constitution of matter. The authors of this paper show that 

 the ellipticity at a reflecting surface can be appreciably changed 

 by a mechanical change of the medium without influencing the 

 reflecting surface. — Ann. der Physik, No. 2, 1910, pp. 325-342. 



J. T. 



6. Study of Gaseous Suspensions. — Maurice de Broglie 

 refers to the Brownian movement in fluids and calls attention to 

 analogous movements of suspended particles in air or gases. He 

 describes an ultra microscopic arrangement which he uses to 

 study smoke particles. He discusses the effect of an electric 

 field, influence of weight, and the relations of the movements 

 observed to Brownian movements. In smoke, he finds particles 

 of which the radius lies between /xfji and a hundredth of fxfi. — 

 Physik. Zeitschrift, Jan. 15, 1910, pp. 33-39. J. t. 



7. Constitution of the Electric Spark. — The work of Schuster 



and Hemsalech has been continued by T. Royds, under the 



advice and suggestion of Schuster and Rutherford. The method 



of observation consisted in focussing the spark upon a rapidly 



revolving photographic film. The velocities of metallic vapor 



caused by the spark between different terminals are given in a 



m 

 table. In general these velocities are within 10 3 — . The author 



° 8 



shows that the vaporization of the metallic electrode is simul- 

 taneous with the pilot or initial spark. Two simultaneous veloci- 

 ties were obtained in the case of calcium vapor. — Phil. Mag., 

 Feb., 1910, pp. 285-290. J. T. 



8. Cadmium Amalgams and the Weston Normal Cell. — In a 

 communication from the National Physical Laboratory, F. E. 

 Smith reviews the work of previous writers on this subject and 

 submits his own measurements. There are many suggestions 



.deduced from his work. Among them is the advice that the 12^- 

 per cent amalgam be replaced by a 10 per cent amalgam. — Phil. 

 Mag., Feb., 1910, pp. 250-276. J. t. 



