Reactions of certain Synthesised Proteid-like Substances. 337 



it is shown that this assumption does not introduce any serious error 

 within the limits of volume considered. We tnen find it possible to 

 integrate the resulting differential equation, and the complete primi- 

 tive enables us to draw a set of adiabatic curves. We believe that 

 this is the first time adiabatic curves have been obtained for any 

 substance except perfect gases. 



A mathematical discussion is added as to what extent the equations 



E = gT-h 

 and yjb = constant, 



can be considered as strictly true, and not merely approximate. 



The experimental results for liquid ether form an appendix to the 

 paper. 



"The Chemical and Physiological Reactions of certain 

 Synthesised Proteid-like Substances. Preliminary Com- 

 munication." By JOHN W. PICKERING, D.Sc. (Lond.). 

 Communicated by Professor HALLIBURTON, F.R.S. Re- 

 ceived November 10, Read December 10, 1896. 



The experiments of Professor Grimaux,* made more than ten 

 years ago, have until recently attracted but little attention amongst 

 English physiologists, although that investigator has synthesised a 

 series of colloidal substances which, in their chemical characteristics, 

 show striking similarities to proteids. 



Working alone, and in collaboration with Professor Halliburton, If 

 have shown that three of the substances synthesised, viz., the 

 " Colloids amidobenzoic A and B," formed by the interaction of 

 phosphorus pentachloride and meta-amido-benzoic acid at 125 C., 

 according to the details described in Grimaux's papers, and the 

 " colloide aspartique " formed by the passage of a current of dry 

 gaseous ammonia over solid aspartic anhydride heated to 125 C., not 

 only give the leading chemical reactions of proteids, but when intra- 

 venously injected into dogs, cats, or pigmented rabbits, cause 

 extensive intravascular coagulation of the blood, in a manner indis- 

 tinguishable from the physiological action of nucleo-proteids. When 

 injected into the veins of albino rabbits or into the vascular system 



* G-rimaux, ' Comptes Kendus,' vol. 93, p. 771, 1881 ; ibid., vol, 98, p. 105, 1884 ; 

 ibid., vol. 88, p. 1434 and p. 1578. 



t Pickering, ' Journ. Pliysiol.,' vol. 14, p. 341, 1893 ; ' Comptes Eendus,' vol. 120, 

 p. 1348, 1895; 'Physiol. Soc. Proc.,' Feb. 1.6, 1895 ('Journ. Physiol.,' vol. 17) ; 

 4 Journ. Physiol.,' vol. 18, p. 54, 1895; Hid., vol. 20, p. 171, 1896; ibid., vol. 20, 

 p. 310 ; Halliburton and Pickering, ' Journ. Physiol.,' vol. 18, p. 285, 1895. 



