282 OF NUTRITION. 



NOTES. 



(A) The redness imparted to the bones by feeding animals 

 with madder, does not prove that the matter of the bones is con- 

 stantly changing ; because the opinion that the madder unites 

 with the phosphate of lime in the blood and thus reddens all the 

 bony matter subsequently deposited, is erroneous. Mr. Gibson 

 proved, by numerous experiments, that the serum has a stronger 

 affinity than the phosphate of lime, for madder. The serum being 

 charged with madder, the phosphate of lime of the bones, al- 

 ready formed, seizes the superabundant madder and becomes 

 red. If the madder is no longer given to the animal, as it is 

 continually passing off with the excretions, the stronger attraction 

 of the serum draws it from the bones, and they re-acquire their 

 whiteness.* 



(B) The constant renewal of the epidermis is demonstrated 

 by wearing black silk stockings next the skin. That the hair 

 and nails not only grow perpetually, but are even reproduced, is 

 certain from the great quantity of the former which falls off 

 the head whole if worn long, while a good head of hair still con- 

 tinues ; and from the renewal of the latter, after the loss of a 

 good part of a finger. I lately attended a middle-aged woman, 

 in St. Thomas's Hospital, who had lost nearly the whole of the 

 first phalanx of a finger, and yet the stump was tipped by a nail, 

 though certainly a clumsy one. An instance of a nail at the end 

 of the stump, after the complete removal of the first phalanx, 

 may be seen in the London Medical and Physical Journal, f 

 Tulpius declares he has seen examples after the loss of both the 

 first and second phalanges (in secundo et tertio articulo).J The 

 glans penis (in truth a mere continuation of the corpus spon- 

 giosum urethrse) was entirely renewed in a case described in the 

 Edinburgh Medical and Physical Essays. § Nothing more can, 



• Manchester Memoirs, vol. L f 1817. 



X Observation™ Medica. iv. 56. § Vol. v. 





