Miscellaneous Intelligence. 471 



2. The Temperature of Mars : a Determination of the Solar 

 Seat recorded • by Pjercival Lowell, Proc. Amer. Acad., xlii, 

 651-667. — The author discusses the temperature of Mars, taking 

 into account not simply the question of distance from the sun, 

 but also the other factors which may be supposed to affect the 

 problem. The results reached are as follows : The mean temper- 

 ature is 48° F. (9° C.) ; the boiling point of water 111° F. (44° C); 

 the amount of air per unit surface 2/9 of the earth's, involving 

 a pressure of 7 inches (177 mm ) ; the density of the air at the sur- 

 face 1 / 12 of the earth's, or 2-5 inches (63 mm ). 



3. The Evolution of Matter, Life, and Mind; by W. Stew- 

 art Duncan. Pp. 250. Philadelphia, 1907 (Index Publishing- 

 Co.). — In an earlier volume entitled "Conscious Matter," published 

 some twenty-five years ago, the author, as he now states, 

 "attempted to lay the foundation of a clearer method of explain- 

 ing mental activity or psycho-physical phenomena. ... In that 

 little volume reasonable means were taken to bridge the chasm 

 between the mental and physical, by claiming for all Energy in 

 Receipt a new name, that of Subjectivity ; the elementary unit 

 of which is Feeling. Feeling and Energy were contended to be 

 alternate states of matter everywhere. Feeling was given out as 



Energy. Energy was experienced as Feeling " The scope 



of the work now issued will be inferred from this quotation, as 

 also from the following: "The same mode of view is maintained 

 in the present volume with an endeavor to show how it works 

 out in detail throughout the whole history of evolutional crea- 

 tion." 



4. Esperanto in Twenty Lessons ; by C. S. Griffin. With 

 Vocabulary. Pp. 100. New York, 1907 (A. S. Barnes & Co.).— 

 The new universal language invented by Dr. Zamenhoff has had 

 remarkable success thus far. It is claimed, for example, " that 

 with a speaking knowledge of Esperanto a person can travel all 

 over the European continent and be understood everywhere. Nearly 

 one hundred papers are published in the language . . ." Whether 

 the prediction that in the course of a few years scientific works, 

 among others, will be published in Esperanto, as well as in the 

 original language, is to be verified remains to be seen ; but in any 

 case this excellently prepared handbook will be highly valued by 

 many who wish to inform themselves on this interesting subject. 



5. Wellcome' s Photographic Exposure Record and Diary. 

 United States Edition, 1907. Pp. 260. London (Burroughs, Well- 

 come & Co.) and New York (45 Lafayette St.). — Photographers 

 will find in this little handbook and diary many important sug- 

 gestions for their work, dealing particularly with the question of 

 exposure. The Wellcome Exposure Calculator is a simple device 

 by which a rotating disc serves to connect the light-value deter- 

 mined by the month of the year with that due to the special con- 

 ditions existing at the time and with the plate-speed, yielding at 

 once the correct exposure in seconds, or fractions of a second, for 

 the usual stops. The usefulness of the " tabloid " developers is 

 also clearly brought out. 



