Chemistry and Physics. 147 



Historical Introduction, Isomerism and Stereoisomerism, Stereo- 

 chemistry of Unsaturated and Cyclic Compounds, Stereochem- 

 istry of Nitrogen, Isomeric Change, Steric Hindrance, Condensa- 

 tion, The Carbohydrates, Fermentation and Enzyme Action, The 

 Purine Group, The Proteins, The Benzene Theory, The Terpenes 

 and Camphors, The Alkaloids. The book is undoubtedly a very 

 useful addition to our text-book literature. h. l. w. 



7. Radio-activity of Lead and Other Metals. — Prof. J. C. 

 McLennan,' of the University of Toronto, finds that the high 

 activity of lead is due to the presence of impurities, and not to 

 a high intrinsic radiation from the metal. The differences in the 

 conductivity of air confined in vessels of different metals are due 

 to differences in the secondary radiation from these metals. 

 Approximately 9 ions per c.c. per second are generated in free 

 air by the penetrating radiation from the earth. — Phil. May., 

 Dec. 1907, pp. 760-779. j. t. 



8. Production and Origin of Radium. — Prof. E. Rutherford 

 concludes that in the ordinary actinium preparations there exists 

 a new substance which is slowly transformed, into radium. This 

 direct parent of radium can be chemically separated both from 

 actinium and radium. Observations have not determined yet 

 whether this direct parent of radium has any genetic connection 

 with actinium or not. — Phil. Mag., Dec. 1907, pp. 733-749. 



J. T. 



9. Radium Emanation in the Atmosphere near the Earth's 

 Surface. — 'In 1906 Professor Rutherford found that charcoal pre- 

 pared from coca nuts entirely absorbed the radioactive emana- 

 tions, provided they were passed slowly through the charcoal. 

 Professor A. S. Eve, of Montreal, has adopted this method and 

 "finds that the emanation in the atmosphere is absorbed by this 

 kind of charcoal ; and that its magnitude is 80X10 -12 expressed 

 in terms of the amount of radium required to maintain the sup- 

 ply per cubic meter constant. — Phil. Mag., Dec. 1907, pp. 724- 

 733. j. T . 



10. Anomalies in the Behavior of Dielectrics. — A long paper, 

 with abundant references to previous workers, has been published 

 by Egon Ritter v. Schweidler. He finds that Maxwell's theory 

 of non-homogenous structure of the dielectric leads to qualitative 

 correct consequences, but is not available on account of mathe- 

 matical difficulties for quantitative work. It seems that there is 

 no theory at present which comprises all the anomalies obsei - ved. — 

 Ann. der Phys., No. 14, 1907, pp. 711-770. j. t. 



11. Effect of Pressure upon Arc Spectra. — In a paper by W. 

 Geoffrey Dtjffield, communicated to the Royal Society by Prof. 

 A. Schuster, July 4, 1907, the author shows that in the case of 

 iron all lines become broader. The broadening may be symmet- 

 rical or unsymmetrical ; in the latter case the broadening is greater 

 on the red side. With increase of pressure the displacement is 

 toward the red side of the spectrum. The displacement is real 

 and is not due to unsymmetrical broadening. I have shown — 



