#43 Reactions of certain Synthesised Proteid-like Substances. 



The colloid // coagulates only at -52 C. 



Adopting the conclusion of Halliburton that the precipitates ob- 

 tained by the fractional heat coagulation of a proteid substance, 

 correspond with various constituents of that substance, we may 

 possibly conclude that those synthesised colloids which yield frac- 

 tional heat-coagula are mixtures of different colloidal substances. 



Thus the colloid B would consist of two substances which might 

 be designated B x and B 2 , and the colloid ft of three substances, 

 designated colloids /3i, /3 2 , and /3 3 respectively, and the colloid of 

 two substances, ^ and 2 . I have endeavoured to ascertain in the 

 cases of the colloids B! and B 3 and of the colloids /3 1? y3 2 , and fa 

 whether each of these substances will equally induce intravascular 

 coagulation of the blood, when intravenously injected into pigmented 

 rabbits and dogs. 



The method of procedure adopted was briefly as follows : The 

 activity of a solution of the colloid was tested by a control experi- 

 ment. One of the constituents was removed by fractional heat- 

 coagulation and the effect, if any, produced by the intravascnlar in- 

 jection of the remaining colloid in solution w r as tested.* The follow- 

 ing is the record of some of the results obtained : 



Colloid B 2 after a removal of colloid B t will, if intravenously 

 injected, induce intravascular coagulation in pigmented rabbits, and 

 if slowly injected in minute doses a "negative phase " in dogs. 



Colloids $8 and /3 3 will still, after the removal of colloid j3 h induce 

 intravascular coagulation in pigmented rabbits, although a much 

 larger dose is required after the removal of (3i and /3 2 than if the 

 mixture of the three substances is injected, if only fa is removed the 

 activity of the mixture is not impaired. From this I conclude that 

 fa and /3 3 are the active constituents of the colloid mixture I have 

 designated as the colloid /3. There is apparently no difference in the 

 tendency to induce a "negative phase" in dog's blood after the 

 removal of fii and /3 2 from the solution. 



III. Other Properties of the Synthesised Colloids. 



The influence of these substances on red and white blood cor- 

 puscles, and on extravascular 1 per cent, sodium carbonate plasma 

 will be described in a subsequent paper. 



IV. Concluding Remarks. 



It is evident from the observations recorded in the preceding 

 pages, that if certain derivatives of proteids, and other substances of 



* The solution after removal of one of its constituents by fractional heat- 

 coaguiation, was evaporated down in vacuo until it had the same specific gravity as 

 the original solution. 



