110 GLANDS IN HEALTH AND DISEASE 



also the following more tangible result: the ewe- 

 lamb covered by him in September, 1918, dropped a 

 vigorous lamb in February, 1919. There is nothing 

 in the fact to cause surprise. Old animals, like 

 very aged men, occasionally still possess spermato- 

 zoids which are altogether alive, but it is the atro- 

 phy of the internal secretive glands which prevents 

 their experiencing the sexual appetite and mani- 

 festing their virility." 



Dr. Voronoff's next procedure with the rejuve- 

 nated animal was excellent from the scientific 

 standpoint. He removed the graft. Three months 

 later the animal had completely aged. Then he re- 

 implanted another graft from the testicle of a 

 younger animal. Once again the animal showed 

 signs of rejuvenation. Nothing in the whole book 

 approaches in value this particular experiment. 



At the time of writing the graft had been in its 

 place for a year and the animal was still in excel- 

 lent condition. Even if we could reason by analogy, 

 which in this instance we should be careful not 

 to do we could hardly draw any far-reaching con- 

 clusions as to the length of time old age could be 

 warded off in man. 



Having successfully performed experiments on 

 animals, Dr. Voronoff next turned his attention to 

 man. Here a difficulty immediately arose. How 

 was he to get a healthy young man's gland in order 

 to implant it into an old man's system? If only 



