SCIENCE 



Friday, ]Sro\'EMBER 23, 1917 



CONTENTS 



Electromerism, a Case of Chemical Isomerism 

 resulting from a Difference in Distribution 

 of Valence Electrons: Professor Lauder 493 

 "William Jones 



decent Physiology and the War: Professor 

 Charles S. Sherrington 502 



Fre-medical Training in Chemistry: Dr. Fred- 

 erick S. Hammett 504 



Scientific Events: — 

 British Experimental Station for Fuel Me- 

 search ; The Columbian Institute; Aioard of 

 the John Scott Legacy Medals and Pre- 

 mimns and of the Edward Longstreth 

 Medal of Merit 506 



Scientific Notes and News 509 



University and Educational News 510 



Discussion and Correspondence : — 



An Extraordinary Bainfall Eecord: Pro- 

 fessor Douglas H. Campbell 511 



Quotations : — 

 The Bockefeller Health Researches 512 



Sdentifio BooTcs: — 



Thompson on Growth and Form: J. P. 

 McM. Boas on Tsimshian Mythology: 

 John E. Swanton. Trelease's The Genus 

 Fhoradendron: George G. Hedgcock .... 513 



Mechanical Properties of Wood 516 



Special Articles: — 

 A Convenient Nerve Holder: S. S. Max- 

 well. The Urine of the Horned Lizard: 

 A. O. "Weese 517 



Societies and Academies: — 



The American Mathematical Society: Pro- 

 fessor F. N. Cole 518 



MSS. intended for publication and books, etc., intended for 

 review ahoula be sent to The Editor of Science, Garrison-on- 

 Hudson, N. f. 



ELECTROMERISM, A CASE OF CHEM- 

 ICAL ISOMERISM RESULTING FROM 

 A DIFFERENCE IN DISTRIBUTION 



OF VALENCE ELECTRONS i 

 Eecent advances in our knowledge of 

 the structure of matter have made it pos- 

 sible for an organic chemist to address a 

 group of non-organic chemists and of 

 phj'sicists upon this subject without apolo- 

 gizing. During a period which is not far 

 behind us in the past, not only the validity, 

 but, possibly, even the utility of employing 

 structure conceptions requiring atoms and 

 their arrangements was brought into ques- 

 tion ; so that the organic chemist, who has 

 maintained an abiding faith in atoms and 

 a confidence in his ability to decipher some- 

 thing of their arrangements in molecules, 

 became aware of an indulgent smile when- 

 ever he broached this subject except in the 

 company of his own confreres. 



With this inheritance, it is natural to ex- 

 pect that the organic chemist would wel- 

 come any discoveries which make our con- 

 ception of atoms and of the mechanism by 

 which atoms combine to form molecules 

 more concrete ; and that he would be among 

 the first to seek to apply these concepts to 

 special problems in his own field. 



With a feeling of keen satisfaction, 

 therefore, we learn through the work of 

 Bragg that, in a diamond crystal, each car- 

 bon atom is surrounded by four other car- 

 bon atoms placed equidistant from it. 

 These atoms are grouped around the cen- 

 tral carbon atom as the four corners of a 

 1 An address prepared for the sympositim on the 

 "Structiire of Matter," held at the meeting of the 

 American Association for the Advancement of 

 Science in New York City, December, 1916. 



