94 PHYSIOLOGY AND NATIONAL NEEDS 



tained it because it did not escape from the vessels ; 

 and he found that the feeble heart when given this 

 fluid to contract upon responded and drove it 

 through the tissues, so that the supply of oxygen 

 to them was restored, and recovery was rendered 

 possible, provided the condition of shock had not 

 gone on too long. His method has been applied 

 in the field, and has been proved to be of great 

 service in many cases. 



In the light of these observations the patient's 

 craving for water is explained. It is due to there 

 being too little blood in effective circulation, and 

 the free administration of water which is in part 

 absorbed into the blood serves in slight cases to 

 raise the blood pressure sufficiently to allow of 

 recovery. 



The sense of cold is due to the stagnation of 

 the blood — the warm blood from the interior is not 

 sent to the skin, where alone are placed the nerve 

 structures which when stimulated give us the 

 sense of cold. 



Physiologists have thus explained the main 

 disturbance involved ; and although their evidence 

 of the accumulation of blood in the capillaries 

 cannot be considered conclusive, they have been 

 able to suggest a line of treatment which has 

 proved of the greatest service. 



The first example I have given shows how by 

 the investigation of physiologists the cause of the 



