SCIENCE. 



Editorial Committee : S. NEWcoini, JIathematics ; R. S. Woodward, Mecbanics ; E. C. Pickering, As- 

 tronomy ; T. C. Mexdexhall, Physics ; R. H. Thurston, Engineering ; Ira Remsen, Chemistry ; 

 Joseph Le Conte, Geology; W. M. Davis, Physiography; O. C. Marsh, Paleontology; W. K. 

 Brooks, Invertebrate Zoology ; C. Hart Merriam, Vertebrate Zoology ; N. L. Briiton, 

 Botany ; Henry F. Osbohn, General Biology ; H. P. Bowditch, Physiology ; 

 J. S. Billings, Hygiene ; J. McKeen Cattell, Psychology ; 

 Daniel G. Brinton, J. W. Powell, Anthropology. 



Friday, March 22, 1895. 



CONTENTS: 



Argon : IR A Remsen 309 



The Fundamental Difference between Animah ami 

 Planln ; CHARLES S. MiNOT 311 



The Best Order of Topics in it Tieo-i/eam' Conrse of 

 Annlnm;/ in a Medieal School: FREDERIC Henry 

 Gerrish 312 



Current Nolcs on Physiography {IV. ) : W. M. 

 DA\as 318 



Annual Reception of the Nexe York Academy: 

 Henry F. Osbohn 321 



Correspondence : — 324 



An International Seientijie Catalogue and Con- 

 grefts : HoRATIO Hale. 



Scientific Literature : — 326 



Brinton's Primer of Mayan Hieroglyphics : FRED- 

 ERICK Starr. Yro's Slcnm Engine: R. H. 

 Thl'R.ston. Life of Dcitn Bueklund : A. S. 

 Packard. Geology. 



Notes and Xeivs : — 331 



Biology: Welding of Iron ; The .Joint Commission 

 of Scientific Societies of Washington ; General. 



Societies and Academies : — 334 



Biological Society of Washington. 



Scientific Journals 335 



New Books 336 



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

 for review should be sent to the responsible editor, Prof. J. 

 McKeen Cattell, Garrison on Hudson, N. Y. 



Subscriptions and advertisements should be sent to Science. 

 41 N. Queen .St.. Lancaster, Pa., or 41 East 49th St., New York. 



ARGON. 

 The plain facts concerning argon are 

 these: For some time past Lord Rayleigh 

 has been engaged on relincd work involving 

 the weighing of various gases. Last year he 

 found that the nitrogen obtained from the 

 air is a little heaNier than that made from 

 definite chemical compounds. This led him 

 to further exi)eriments and, at the same 



time. Professor W. Ramsay, of University 

 College, London, also undertook experi- 

 ments with the object of explaining, if pos- 

 sible, the discrepancy. The general method 

 of work consisted in pas.sing air, first through 

 substances that have the power to remove 

 those constituents that are present in small 

 quantities, such as water vapor, carbonic- 

 acid gas, etc., then through a heated tube 

 containing copper. The oxj^gen of the air 

 unites with the heated copper, and what 

 has hitherto been regarded as nitrogen 

 remains uncombined. This ' atmospheric 

 nitrogen ' was subsequently treated in three 

 different ways for the purpose of removing 

 the nitrogen from it. 



(1) It w^as drawai through clay pipes in 

 the hope that, if the gas is a mixture, one 

 of the constituents would pass through the 

 porous material more easilj^ than the other, 

 and at least a partial separation be thus 

 effected. While something was accom- 

 plished in this way, the experiment was on 

 the whole unsatisfactoiy. 



(2) The ' atmospheric nitrogen ' was 

 mixed with oxygen in a vessel con- 

 taining caustic alkali, and electric sparks 

 were passed through the mLxture. Under 

 these circumstances the oxygen united with 

 nitrogen and formed a compound which is 

 soluble in alkali. After no further absorp- 

 tion of nitrogt'n could be effected by spark- 

 ing, any unchanged oxygen present was re- 

 moved, and there was then found a residue 



