474 Dr. T. Carnelley on the 



Specific Magnetism. 



=+0-181 (Faraday), 

 S =—1*14 (Becquerel), 



Se = 



— 1-65 



?? 



N = 



+ o-oos 



1 (Faraday) 7 



P = 



Sb = 



- 1-64 



- 4-10 



(Becquerel), 



Bi = 



-22-67 



?? 



H = 



Cu = 



-0-001 

 -1-68 



(Faraday), 



Ag = 

 Au = 



-2-32 

 -3-47 



71 



Physiological Action. — The results obtained by Gamgee, as 

 regards the physiological action of ortho-, pyro-. and meta- 

 phosphoric acids, and also of the salts of vanadic acid, appear 

 to show that there is likewise some regular connexion between 

 chemical constitution and physiological action. 



Chemical Affinity. Mutual Displacement of Halogens. — 

 Potilizin (Chem. Centr. 1876. p. 577) has determined the 

 amount of CI displaced by Br when the latter is allowed to act 

 upon metallic chlorides : and he found that the amount of CI 

 replaced by Br was proportional to the atomic weights of the 

 metals with which the CI was combined, provided they had 

 the same atomicity in the respective compounds : thus 



Per cent, of CI replaced by Br in : — 



r T fXaCl KC1 AeCl 



Group I. | 7 . 16 12 . 54 33 - 34 



Group II. < 



CaClo SrClo BaClo HgCl, PbCl, 

 3-2 6-64 9-86 15-16 15-64 



Gustavson (Ann. Chim. Phys. (5) ii. p. 200: TTatts's Diet. 

 viii. p. 429) has also determined the amount of mutual re- 

 placement which occurs when CC1 4 or CBr 4 acts upon various 

 other bromides or chlorides. The following Table represents 

 the percentage of the double decomposition which takes place 

 when the several pairs of bodies are heated together in sealed 

 tubes to 150 c -200°:— 



