METABOLISM. 



453 



venesection and transfusion would theoretically be the proper 

 treatment to remove disorganised blood and poison, and to 

 replace them by healthy corpuscles and plasma. But this is 

 manifestly very rarely practicable. All that can be done, as a 

 rule, is to sustain the circulation and respiration, by general 

 stimulants and artificial respiration, and thus preserve vitality 

 by means of the oxygen and haemoglobin that may still remain 

 active. In every case it will be proper to do this until trans- 

 fusion can be undertaken. 



SYNOPSIS OF SUBSTANCES WHICH ACT ON THE BLOOD. 



CHAPTER IX. 



METABOLISM THE ACTION OF MEDICINES ALTERATIVES. 



WE now pass on to consider the process of nutrition or metabo- 

 lism, that is, the activity of the tissues, the development of force 

 by protoplasm in the presence of blood. We shall find that this 

 subject has an important bearing on the action and uses of 

 many drugs and other therapeutic measures. 



I. PHYSIOLOGICAL RELATIONS. 



The best means of comprehending the obscure subject of 

 metabolism is to take the instance of a muscle. A muscle has 

 a definite structure ; enjoys a free supply of blood ; displays 

 force during the period of its contraction, namely, mechanical 



