Apeil 30, 1915] 



SCIENCE 



653 



selection of common things discussed under 

 the title, "Molecular Forces and Motions." 

 Here occur discussions of the diffusion of 

 gases, the evaporation, diffusion and capillary 

 action of liquids, crystallization, elasticity and 

 general properties of matter. This introduc- 

 tion covers eight of the seventy-seven sections 

 into V7hich the book is divided, each section 

 containing material enough for one recitation. 

 The order of treatment of the subjects is as 

 follows: Mechanics, Heat, Electricity, Sound, 

 Light. By summarizing at the close of each 

 section the important topics treated therein, 

 and by setting problems which are related to 

 the life of the pupil as well as to the prin- 

 ciples of physics, the authors have made a spe- 

 cial effort to produce a helpful book. Mathe- 

 matical expressions are not avoided, but are 

 used only where they are of apparent advan- 

 tage to the student; indeed this advantage 

 should be the only justification for mathe- 

 matical expressions in either elementary or 

 advanced physics. The illustrations, in both 

 number and selection, are to be commended. 

 The volume is distinctly a text-book, all of 

 which is to be taught in the year's course in 

 physics, save perhaps some of the numerous 

 exercises which are found at the close of each 

 lesson. The value of the work can only be 

 ascertained by experience in the class room, 

 but the spirit of the authors and their appar- 

 ent success in applying it in the preparation of 

 this book must commend the text to the con- 

 sideration of every high-school teacher. 



G. W. Stewart 



SPECIAL ARTICLES 



ANTAGONISM AND BALANCED SOLUTIONS ^ 



The term antagonism came into general 

 physiology from medicine, where it was used 

 in the seventies by Rossbach, Luchsinger and 

 others to designate the opposing types of phys- 

 iological action produced by certain chemical 

 substances. Luchsinger, Langley, Sydney 

 Einger and others applied the term to that 

 type of physiological situation seen in the 

 opposite effects produced by atropine and pilo- 



1 Published by permission of the Secretary of 

 Agriculture. 



carpine on the sweat glands. One alkaloid, 

 atropine, stimulated the activity of the gland, 

 the other depressed it, and one effect could be 

 made to partly or wholly supersede the other 

 by the proper adjustment of the concentration 

 and quantity of alkaloidal solutions used. It 

 was found possible to establish physiologically 

 equivalent quantities of each alkaloid which 

 would exactly nullify the action of the other 

 when applied to the tissue, and a given physio- 

 logical result could be calculated from given 

 quantities of the antagonistic substances. As 

 Luchsinger saw it, the action of these sub- 

 stances was like algebraic plus and minus and 

 came back to mass action (Massenwirkung) 

 and aiSnity, a view accepted in effect by Lang- 

 ley and Einger. In these experiments phys- 

 iological antagonism meant opposing action on 

 a definite function as a criterion. Contraction 

 of the frog's heart, action of the salivary 

 gland and contraction of the pupil of the eye 

 were examples of such criteria. 



In work of this type the antagonists were 

 used in simple solutions applied serially to the 

 tissues in question, and the fact of antagonistic 

 action was demonstrated by the disappearance 

 of the action characteristic of the first sub- 

 stance upon the application of the second 

 substance. The simultaneous application of 

 the antagonistic substances seems not to have 

 been made. 



Work of this type developed a number of 

 important differences in the behavior of sup- 

 posed antagonists. Luchsinger found when 

 the activity of the sweat gland of the cat was 

 used as a criterion that pilocarpine and 

 atropine produced opposite actions and that 

 each was able to efface the other as wave- 

 hollow effaces wave-crest or as algebraic plus 

 effaces algebraic minus. This ability of each 

 to efface the other and to produce the opposite 

 physiological state in either order of applica- 

 tion Langley proposed to call mutual antag- 

 onism. 



This clean-cut, two-way, type of result, 

 however, was not the rule, and for two chief 

 reasons. (1) It was unusual that the action of 

 two substances should cover precisely the same 

 area of function and thus fully oppose each 

 other throughout their effects. As a result. 



