1 I I SCU nthi<- Inti llnji ur, . 



spectrograms of the stars with those obtained from the artifici- 

 ally prepared gas. When taken with the same linear dispersion, 

 the bands on the juxtaposed spectrograms agree perfectly in 

 position, intensity and character. The photographs of the solar 

 spectrum corresponding to altitudes of 55°, 30°, 10°, 4°, and 1° 

 show a series of narrow ultra-violet absorption bands thai 

 increase in number and intensity as the altitude of the sun 

 decreases. These bands also coincide with the ones obtained 

 with laboratory ozone. It should also be added that the bands 

 recorded on stellar photographs are independent of the spectral 

 type of the stars. Consequently, Fowler and Strutl have proved 

 conclusively that the bands in the stellar spectrograms owe their 

 origin to telluric ozone. The full-page plate at the end of the 

 paper is an excellent reproduction, and it merits the attention 

 of those who are interested in the subject. — Proc. Boy. Soc, 93, 

 577, 1917. ii. s. r. 



6. Mathematics for Agriculture and General Science; by 

 Alfred Monroe Kenyon and William Vernon Lovitt. Pp. 

 vii, 357, with 135 figures. New York, 1917 (The Macmillan 

 Co.). — This book is designed as a text in freshman mathematics 

 for students specializing in agriculture, biology, chemistry, and 

 physics, jbu colleges and in technical schools. It is intended for 

 a course of three hours a week for one year, but it can be used 

 for a half-year course. 



The scope of the text may be inferred from the following list 

 of subjects : review of equations, graphic representation, loga- 

 rithms, trigonometry, land surveying, statics, small errors, conic 

 sections, variation, empirical equations, the progressions, annui- 

 ties, averages, permutations and combinations, the binomial 

 expansion — laws of heredity, the compound interest law, proba- 

 bility, correlation, and maxima and minima. 



The exercises for solution by the reader constitute one of the 

 most prominent features of the book. They include many data 

 taken from agricultural and other experiments, carefully selected 

 to stimulate independent thinking and to show the application of 

 general principles to problems which actually arise in everyday 

 life, and in the solution of which progressive men and women 

 are vitally interested. The number of exercises is unusually 

 large (1257, often with subdivisions), and they contain a wealth 

 of material. The volume closes with tables of logarithms, of 

 trigonometric functions, and of other useful constants. The 

 typographical work, composition, text-tables, and diagrams are 

 excellent, and the book seems very well adapted to the needs of 

 those to whom it is addressed. n. s. u. 



7. The Radioactivity of Meteorites; by T. T. Quirke and 

 Leo Finkelstein. — The following corrections should be made in 

 this article in the September number, 1917, vol. 44, pp. 237-242: 



Page 237, date of footnote should be 1906. 

 Page 241, radioactivity of Coahuila meteorite should be 7-69 

 x 10- 14 . 



