1917] on Recent Physiology and the War 3 



were sliown to l)e : liarmlessness in respect of avoidance of causing 

 slotting in the circulation ; restoration of the volume of the fluid in 

 the circulation ; maintenance of the due degree of viscosity of the 

 circulating fluid, since on that factor depends the arterial and capillary 

 pressure ; and, finally, preservation of the balance between the 

 osmotic pressure of the fluid inside the blood-vessels and outside in 

 the tissues. It was shown that considerable success had been 

 reached in this problem by the experiments of Professor Bayliss and 

 others. 



A final point dealt with was the treatment of tetanus by adminis- 

 tration of " anti-tetanus serum." This serum is obtained from the 

 blood of horses which have been subjected to gradually-increasing 

 doses of tetanus-toxin, the poison produced by the tetanus-bacillus. 

 The high efficiency of this anti-toxic serum when used as a prophylactic 

 was first demonstrated on man on a large scale by its employment 

 in the first autumn of this war. Curves illustrating the statistics 

 were shown. The severe outbreak of tetanus which ensued in the 

 troops at the outset of the campaign was checked and practically 

 stopped almost instantaneously by the orders that every wounded 

 man, as soon as possible after being wounded, that is to say, at the 

 first field casualty-station, should receive a small injection of anti- 

 tetanus serum from the immunized horse. But the efficacy of the 

 serum when once signs of tetanus have appeared in the patient is 

 far less satisfactory. The remainder of the Lecture was devoted to 

 discussion of why this should be, and in what ways the difficulty may 

 be, at least in part, overcome. 



[C. S. S.] 



B 2 



