SCIENCE 



Editorial Committee : S. Newcomb, Mathematics ; E. S. Wood-waed, Mechanics ; E. C. Pickering 



Astronomy; T. C. Mendenhall, Physics; R. H. Thurston, Engineering; IKA Eemsen, Chemistry; 



J. Le Conte, Geology; W. M. Davis, Physiography; 0. C. Marsh, Paleontology; W. K. Brooks, 



C. Hart Meeriam, Zoology; S. H. Scuddke, Entomology; C. E. Bessky, N. L. Britton, 



Botany; Heney F. Osboen, General Biology; C. S. Minot, Embryology, Histology; 



H. P. Bowditch, Physiology; J. S. Billings, Hygiene ; J. McKeen Cattell, 



Psychology; Daniel G. Brinton, J. "W. Powell, Anthropology. 



Friday, Febeitary 24, 1899. 



CONTENTS: 



The Recently Discovered Oases and their Relation to 

 the Periodic Law ; Professor William Ram- 

 say 273 



A Case of Convergence: Professor Carl H. 

 Eigenmann 280 



Eeprodiictive or Genetic Selection : PROFESSOR 

 Kael Pearson 283 



The New Tork Sleeting of the American Physiolog- 

 ical Society : Peofessoe Frederics. Lee 286 



Scientific Books : — 



Thomson on the Discharge of Electricity through 

 Gases : Peofessoe Eenest Meeeitt. Sehdfer's 

 Text-book of Physiology : PEOFESSOE GRAHAM 

 LusK. Scientific Year-hooks. General. Books 

 Received 289 



Scientific Journals and Articles 293 



Societies and Academies : — 



Washington Botanical Club : Dr. Charles Louis 

 Pollard. Torrey Botanical Club : E. S. Bur- 

 gess. Philosophical Society of Washington : E. 

 D. PllESTOiSr. Alabama Industrial and Scientific 

 Society: Professor Eugene A. Smith 294 



Discussion and Correspondence : — ■ 

 Eiherion: Peofessoe W. S. Franklin 297 



Notes on Inorganic Chemistry: J. L. H 297 



Current Notes on Sleteorology : — 



Waterspouts off the Coast of Neio South Wales : 

 Annual Report of the Chief of tlfe Weather Bu- 

 reau : Meteorological Chart of the Great Lakes : 

 Notes: R. De C. Ward 298 



Current Notes on Anthropology: — 



Megalithic Monuments : The Meaning of Primitive 

 Ornament ; Genealogy as a Branch of Anthropol- 

 ogy : Professor D. G. Brinton 299 



Scientific Notes and News 300 



University and Educational News 304 



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

 for review ehould be sent to the responsible editor, Profes. 

 80r J. McKeen Cattell. Garrison-on-Hudson N. Y. 



TBE RECENTLY DISCOVERED GASES AND 



THEIR RELATION TO THE PERIODIC 



LA IF.* 



Gentlemen : It is well known to you 

 all how the remarkable observation of Lord 

 Rayleigh that nitrogen from the atmos- 

 phere possesses a greater density than that * 

 prepared from ammonia or nitrates led to 

 the discovery of argon, a new constituent of 

 the air. I need not say that had it not 

 been for this observation the investigations 

 of which I shall speak this evening would 

 never have been carried out, at least not by 

 me. You also, doubtless, will remember that 

 the search for some eompound of argon was 

 rewarded, not by the attainment of the 

 quest, but by the discovery, in clevite and 

 other rare uranium minerals, of helium, an 

 element whose existence in the chromo- 

 sphere of the sun had already been sus- 

 pected. And, further, I hardly need to re- 

 call to your minds that the density of 

 helium is in round numbers 2, and that of 

 argon 20, and that the ratio of specific heats 

 of both these gases, unlike that of most 

 others, is 1.66. 



From these figures it follows that the 

 atomic weight of helium is 4 and that of 

 argon 40. It is true that in many quarters 

 this conclusion is not admitted, but I have 

 always thought it better to recognize the 



*Address delivered by Professor William Ramsay 

 before the Deutschen chemisohen Gesellsohaft, De- 

 cember 19, 1898. Translated by J. L. H. 



