94 Scientific Intelligence. 



5. American Chemistry; by Harrison Hale. 8vo, pp. 215. 

 New York, 1921 (D. Van Nostrand Company). — We find in this 

 book a series of essays in popular style giving very interesting 

 accounts of various achievements in applied chemistry and their 

 importance in some of the large industries. There are 63 good 

 illustrations, many of them of full-page size; there are many 

 striking statistical statements and comparisons ; there are numer- 

 ous references to the literature, and the topics discussed are of 

 great general interest. The book is, therefore, a useful one for 

 the general reader with scientific inclinations, and it appears to 

 be well suited for arousing the interest of students. h. l. w. 



6. Report on Atomic Structure. — The report of a committee 

 on Atomic Structure appointed by the National Research Coun- 

 cil and consisting of Professors David L. Webster of Stan- 

 ford University, and Leigh Page of Yale University, has 

 been published by the above named body. In the first part, 

 entitled The Present Conception of Atomic Structure, Professor 

 Webster has discussed the evidence as to the existence of electrons 

 and nuclei; the number of electrons in the atom; the specula- 

 tions of Lewis and Langmuir as to the position of the electrons as 

 deduced from chemical statics; Bohr's theory of energy levels, 

 and Parson's hypothesis as to the forces holding electrons in their 

 places. Various questions as to the structure and dynamics of 

 the nucleus raised by radioactive data, and the significance of 

 the data of radiation and chemical dynamics as bearing on the 

 structure and dynamics of the electron, are also reviewed. The 

 author inclines to the radical view that in this field the law of 

 the conservation of energy is only statistical. 



The second and longer part of the report, by Professor Page, 

 is devoted to The Dynamical Theory of Atomic Structure. The 

 author shows how far the postulate of electrons revolving about 

 a central nucleus, and the quantum theory, are able to account 

 quantitatively for the spectroscopic data. The various topics 

 treated are the spectra of hydrogen and similar elements, X-ray 

 spectra, the Kossel relations, the Stark effect, the Zeeman effect 

 and the Ritz formula. — Bull. Nat. Research Council 2, 336, 1921. 



F. E. B. 



7. Velocity of Sound at High Temperatures. — A research 

 published under the above title by Messrs. H. B. Dixon, C. Camp- 

 bell, and A. Parker, was undertaken with the object of arriving 

 at formulas for the variation of the specific heat of gases with the 

 temperature, which might be applicable to the extremely high 

 temperatures reached in explosions. The result forms an 

 important contribution to the knowledge of the gradients of 

 these curves. The sound method was chosen chiefly for the rea- 

 son that the velocity of sound in a heated gas gives the ratio of 

 the specific heats at the temperature of the experiment, and not 



