nS Notices of Books. [January, 



both its feet. Again, reflex action cannot be set up without a 

 suitable stimulus. The stimulus applied to one leg set up reflex 

 action in that leg, or perhaps, by co-ordination, of the muscular 

 movements in the two legs ; but, when one foot was cut off, what 

 caused the nature of the motion to change, and a new set of 

 muscles to be called into action, with such precision as to apply 

 the foot to an unaccustomed part of the body ? This is the work 

 of consciousness ; first to hnoiv that the one motion failed to 

 produce an effect aimed at, next to change the motion so as to 

 produce the desired effect. The experiment is described as if all 

 this were really done by reflex action ; but, if so, then what need 

 have we of consciousness in animals at all, and why ma}- not all 

 their motions and actions during life be so produced ? If the 

 experiment, as recorded, is strictly accurate, it appears to me to 

 demonstrate consciousness and volition, on the part of the frog, 

 without a brain, — a fact by no means incredible in itself, but one 

 which, if established, might have important consequences. 



The book is admirably illustrated, both by woodcuts and by a 

 number of photographs representing the most characteristic 

 expressions. It is written with all the author s usual clearness 

 and precision ; and although some parts are a little tedious, from 

 the amount of minute detail required, there is throughout so 

 much of acute observation and amusing anecdote as to render 

 it perhaps more attractive to general readers than any of Mr. 

 Darwin's previous works. 



Alfred R. Wallace. 



The Hygiene of Air and Water : being a Popular Account of the 

 Effects of the Impurities of Air and Water, their Detection, 

 and the Modes of Remedying them. By William Procter, 

 M.D., F.C.S., Surgeon to the York Dispensary, and formerly 

 Lecturer on Chemistry and Forensic Medicine in the York 

 School of Medicine. London : R. Hardwicke. York : 

 Sampson, Pickering, Johnson, and Tesseyman. 1872. 

 79 PP- 

 The Science of Health in these days is making great advance, 

 and asserts increasing claims for recognition. Its position is a 

 difficult one, for whilst it of necessity lays under contribution 

 the latest discoveries and most abstruse doctrines of modern 

 thought, it must be translated for the comprehension of the bulk 

 of people of the world who have themselves to carry out the 

 precepts which it inculcates. Unfortunately the efforts of the 

 interpreters between Science and the Public are not always suc- 

 cessful, and frothy phrases often constitute a large part of so- 

 called popular manuals, — there is a minute morsel of bread to a 

 prodigious quantity of sack. It is' a relief to turn to Dr. Procter's 

 little book, which seems to give us exactly what we want ; it is 



