544 Scientific Intelligence. 



only that water, carbon dioxide and organic compounds have 

 the necessary properties to make up a suitable environment for 

 living organisms as we know them, but also that the properties of 

 these substances are practically sufficient, in the sense that no other 

 elements with their compounds can maintain a proper environ- 

 ment in a steady state. The author's style is so simple and 

 clear that the volume combines the entertaining advantages of a 

 novel with the instructiveness and rigor of a thoroughly scientific 

 text. h. s. u. 



9. An Introduction to the Mathematical Theory of Heat Con- 

 duction ; by L. R. Ln'gersoll and O. J. Zobel. Pp. vi, 171, 24 

 figures. New York, 1913 (Ginn & Co.). — The aim of the authors 

 has been twofold : (a) to develop the subject with special refer- 

 ence to the needs of the student who has neither time nor mathe- 

 matical preparation to pursue the study at great length, and (b) 

 to point out more clearly and specifically than usual the many 

 applications of which the theoretical results are susceptible. 

 Hence, the text may be used to advantage as the basis of a first 

 course in mathematical physics. The practical applications will 

 also be interesting to geologists and engineers because they 

 include such questions as the cooling of the earth with and with- 

 out radioactive influences, the cooling of lava under water, the 

 tempering of steel, the freezing of concrete, electric welding, fire- 

 proof walls, etc. The usefulness of the volume is increased both 

 by the 61 problems for solution by the student and by the six 

 appendices of thermal data and mathematical formulae and tables. 



h. s. u. 



10. Elements of the Precision of Measurements and Graphical 

 Methods ; by H. M. Goodwin. Pp. 104. New York, 1913 

 (McGraw-Hill Book Co.). — This book is an amplified presentation 

 of the printed " Notes " which the author has used for a number 

 of years in connection with his laboratory classes in the Massa- 

 chusetts Institute of Technology. The degree of advancement 

 of the text may be inferred from the fact that the subject is intro- 

 duced about the middle of the sophomore year, as soon as the 

 students have performed six or eight experiments on fundamental 

 measurements in Mechanics and can handle the elements of the 

 Differential Calculus. 



Part I, pages 7 to 38, deals with the precision of measurements; 

 Part II, pages 41 to 56, relates to graphical methods; and Part 

 III, pages 69 to 98, comprises the solutions of a few illustrative 

 problems together with a list of 79 unsolved questions and problems 

 to be discussed by the student. The appendix includes tables of 

 selected mathematical constants, approximation formulae, squares, 

 cubes, reciprocals, four-place logarithms, and natural and logarith- 

 mic sines, cosines and tangents. The treatment is so very clear 

 and concise, and the material is so wisely chosen that the volume 

 deserves serious consideration by all who are engaged in teaching- 

 laboratory classes in college-grade physics. h. s. u. 



11. Electricity (Home University Library) ; by Gisbert Kapp. 

 Pp. v, 256, 26 figures. New York (Henry Holt & Co.).— In this 



