368 SCIENCE PROGRESS. 



This was previously pointed out by Schafer^ in connection 

 with this same question, and b)- Ringer- in connection with 

 the contractility of the cardiac muscle. No reference is made 

 by Hammarsten to these researches. 



Other inv^estigators who have tackled the question of 

 calcium salts in their relationship to blood coagulation are 

 Alex. Schmidt and Lilienfeld, and the points of difference 

 between these workers and those previously mentioned 

 are cleared up by Hammarsten in the following way : — 



The view of Alex. Schmidt, that lime salts act quali- 

 tatively like other neutral salts such as sodium chloride 

 in promoting coagulation, though in the quantitative sense 

 they are admittedly more powerful, is incorrect. Arthus is 

 unquestionably right when he ascribes to calcium salts a 

 definite and specific action. The action of soluble oxalates 

 is also definite and specific, for by precipitating the calcium 

 salts it neutralises this specific action, and thus inhibits the 

 coaofulation of the blood. Here aoain Arthus is rig^ht, and 

 Schmidt who supposes that alkaline oxalates act in the same 

 manner as excess of other salts of the alkalis in preventing 

 coagulation, is wrong. Arthus, however, goes wrong in 

 the specific action he attributes to the calcium salts. They 

 are not necessary for the change of fibrinogen into fibrin. 

 If a sufficient quantity of fibrin-ferment is present, fibrin- 

 formation goes on as typically and abundantly in solutions 

 which do not contain soluble lime salts (these having been 

 removed by oxalating), as in those which do contain such 

 salts. In this way the analogy drawn by Arthus between 

 fibrinogen and fibrin on the one hand, and caseinogen 

 and casein on the other breaks down. The specific and 

 only action of the lime salts is that discovered by Pekel- 

 haring, in producing the genesis of thrombin or fibrin- 

 ferment, from its precursor, prothrombin. Pekelharing's 

 experiment that the blood-plasma contains a material 



^ In a preliminary note to the Physiological Society (" Proc. Physiol. 

 Soc," p. i8, 1895, in Journal of Physiology, vol. xvii.) Schafer arrived at 

 much the same conclusions regarding this point, and regarding Lilienfeld's 

 thrombosin to be immediately alluded to, that Hammarsten presents more 

 elaborately in his present contribution to the subject. 



'^Practitioner, vol. xxiv., p. 81. 



