DU HAMEL 



49 



" Three pigs were destined to clear up my 

 doubts. The first, six weeks old, was fed for a 

 month on ordinary food, with an ounce daily of 

 madder-juice — garence grappe — put in it. At the 

 end of the month, we stopped the juice, and fed 

 the pig in the ordinary way for six weeks, and then 

 killed it. The marrow of the bones was surrounded 

 by a fairly thick layer of white bone : this was the 

 formation of bone during the first six weeks of life, 

 without madder. This ring of white bone was 

 surrounded by another zone of red bone : this was 

 the formation of bone during the administration of 

 the madder. Finally, this red zone was covered 

 with a fairly thick layer of white bone : this was 

 the layer formed after the madder had been left off. 

 . . . We shall have no further difficulty in under- 

 standing whence transudes the osseous juice that 

 was thought necessary for the formation of callus 

 and the filling-up of the wounds of the bones, now 

 we see that it is the periosteum that fills up the 

 wounds, or is made thick round the fractures, and 

 afterward becomes of the consistence of cartilage, 

 and at last acquires the hardness of bones." 



These results, confirmed by Bazan (1746) and 

 Boehmer ( 1 75 1 ), were far beyond anything that had 

 yet been known about the periosteum. But the 

 growth of bone is a very complex process : the 

 naked eye sees only the grosser changes that come 

 with it ; and du Hamel's ingenious comparison 

 between the periosteum and the bark of trees was 

 too simple to be exact. Therefore his work was 

 opposed by Haller, and by Dethleef, Haller's pupil : 

 and the great authority of Haller's name, and the 

 difficulties lying beyond du Hamel's plain facts, 



D 



