374 SCIENCE PROGRESS. 



ideas, new methods of investigation, and new knowledge in 

 consequence. 



His work fell into three chief lines : — 



i. He attributed to the corpuscular elements of the 

 blood a secondary role in the causation of clotting. He 

 considered that the dibris of corpuscles described by 

 Schmidt is analogous to, if not identical with, a precipitate 

 he obtained by cooling peptone plasma. 1 



2. He attributed to a compound rich in phosphorus a 

 very important part in producing fibrin formation ; he 

 thought this compound was lecithin ; but all recent work 

 tends to show that it is nuclein rather than lecithin, that is 

 the phosphorised compound he was dealing with. 



3. He discovered a material which, when injected into 

 the circulation of a living animal, does produce intravascular 

 coagulation ; and this material is not fibrin-ferment. This 

 third branch of Wooldridge's work is the one which has 

 borne most fruit. 



When these views were first promulgated they met 

 with a good deal of incredulity, and it appeared absolutely 

 impossible to reconcile them with those of the older school 

 of Schmidt and Hammarsten. Pekelharincr was the first 

 to attempt to reconcile the conflicting theories ; and he 

 fancied he had discovered the connecting link in the 

 relationship of calcium salts to the coagulation process. 



Many years ago, Brucke demonstrated that the ash of 

 fibrin always contains calcium. Later (1875), Hammarsten, 

 as we have already noted, pointed out that calcium chloride 

 can take the place of serum-globulin in aiding the action of 

 fibrin-ferment. In 1887, Green found that the coagulation 

 of various forms of plasma is much accelerated by small 

 quantities of calcium sulphate ; and then Drs. Ringer and 

 Sainsbury showed that the same property is possessed by 

 other calcium salts, and to a less extent by the salts of 

 strontium and barium. Freund, who had made somewhat 



1 Peptone plasma is plasma obtained from blood by injecting into the 

 circulation of the animal before death a solution of commercial peptone. 

 The active ingredients in the so-called peptone appear, however, to be 

 albumoses. 



