526 



SCIENCE. 



[N. S. Vol. VIII. No. 199. 



from zinc and sulphuric acid over heated 

 platinum sponge. 



' Oxy-induline— a I^ew Blue Dyestnfif, ' 

 S. P. Mulliken and "W. Kelley. This com- 

 pound, CjgHjgN^Oj, is readily formed by 

 heating amidophenol hydro-chlorate. Sul- 

 phonated it is a fast and direct blue dyestuff. 



* The Benzaldoxines,' F. K. Cameron. 



' On True and Bis-Nitroso Compounds,' 

 E. Kremers. 



Dr. T. W. Richards gave an interesting 

 historical review of the ' History of Phys- 

 ical Chemistry.' In one sense we are not 

 wrong in looking on physical chemistry as 

 a modern invention. While many of the 

 fundamental generalizations are by no 

 means recent, the sharp line drawn thirty 

 years ago between physics and chemistry 

 are but lately erased, and it is well accepted 

 now that the same laws governing one class 

 of phenomena are applicable as well to the 

 other. Boyle, in the seventeenth century, 

 discovered the law of the contraction of 

 gases ; Lavoisier forced the idea of the con- 

 servation of mass upon the scientific world. 

 Dalton, Avogadro, Ampere, Gay-Lussac, 

 Dulong and Petit, Davy and Faraday made 

 great additions to our physico-chemical 

 knowledge. Julien Robert Meyer and 

 Helmholtz acquired a knowledge of con- 

 servation of energy. There were Hittorff's 

 researches on electrolytic conductivity. 

 Wilhelmy, forty years ago, worked on the 

 speed of reactions along the lines suggested 

 by Wentzel and Berthollet. The observa- 

 tions of these savants were used as a basis a 

 decade later by Guldberg and Waage, when 

 they promulgated the law of mass action as 

 a result of the study of the progress and 

 equilibrium of chemical change. Then why 

 should it be regarded as new ? 



The growth of physical chemistry has not 

 been commensurate with that of the other 

 divisions of the science for several reasons, 

 one of which was the necessity for dealing 

 with the little understood subject of solu- 



tions. Van't Hoff having shown that sub- 

 stances in solution follow the same laws 

 governing the aeriform state, and Arrhenius 

 having explained the diiference between 

 solutions conducting electricity and non- 

 conductors, the progress has been very rapid 

 in the last ten years. Professor Richards 

 attributed another cause as summed up in 

 the word ' prejudice.' " Not only have un- 

 tenable theories been held long after their 

 time, but whole fields of study have been 

 neglected by most chemists and physicists 

 because they lay on the border line between 

 the two sciences." 



While higher mathematics is a most valu- 

 able instrument for a physical chemist, 

 there is a serious danger of accurate mathe- 

 matical processes leading to wholly erro- 

 neous conclusions because of incomplete or 

 inaccurate data. One must be an accom- 

 plished physicist, chemist and mathema- 

 tician to obtain the highest results in modern 

 thoretical chemistry, and the number of men 

 having time to acquire the necessary knowl- 

 edge can never be large. Attention was called 

 to the excellent laboratories of Nernst at 

 Gottingen and Ostwald in Leipsic, and it was 

 regretted that America did not have more 

 men devoting themselves to pure science. 



Dr. E. C. Franklin, in his paper on ' Some 

 Properties of Liquid Anhydrous Ammonia,' 

 showed that ammonia resembles water 

 closely in all the properties which give 

 water its unique position as a solvent. It 

 is next to water as a general solvent for 

 salts ; there is a close resemblance in the 

 power of dissociating electrolytes, some 

 salts conducting even better in an ammonia 

 than in a water solution. It forms am- 

 monia of crystallization. Except water, its 

 heat of volitization is greater than that of 

 any other liquid. Its specific heat is as 

 great as water. 



' The Solubility of Di-ionic Salts of Weak 

 Acids in Solutions of Stronger Di-ionic 

 Acids,' A. A. Noyes and David Schwartz. 



