PROLIFERATION OF HEALING 171 



liferate to a great extent when healing occurs anywhere,/ 

 and these w^hite blood-corpuscles formed the objects 

 of our observation in the first instance. What made 

 these cells divide w T e did not know, how they divided 

 was also unknow r n; but we knew that amoeboid move- 

 ments could be excited in them by means of alkaloids. 

 It is an astonishing thing that when any injury 

 occurs, in no matter what part of the body, those 

 neighbouring cells which have not been damaged w T ill 

 immediately reproduce themselves. If the damage is 

 persistent, and healing becomes very chronic in persons 

 over the age of 40, cells may reproduce themselves 

 in a malignant manner, and then they go on dividing 

 and dividing, producing a cancerous growth which 

 ultimately kills the person the part of whose body 

 they are, and whose damaged tissue it was their en- 

 deavour to heal. The first thing to do, undoubtedly, 

 was to try to find the cause of the cell- proliferation 

 of healing. 



