DEPOSITION OF SILVER IN THE TISSUES. 247 



We know that when anyone takes salts ofsilve~, they 

 penetrate into the different tissues of his body ; and if we 

 do not employ them in a really corrosive and destructive 

 manner, the silver penetrates into the elements of the 

 tissues in a state of combination, the nature of/which has 

 not yet been satisfactorily made out, and, when it has 

 been made use of long enough, produces a change of 

 colour at the point of application. A patient who had 

 in Dr. Yon Graefe's out-patient room on the 10th No- 

 vember received a solution of nitrate of silver as a lotion, 

 very conscientiously employed the remedy up to the pre- 

 sent time (17th March) ; the result of which was that his 

 conjunctiva assumed an intensely brown, nearly black 

 appearance. The examination of a piece cut out of if 

 showed that silver had been taken up into the paren- 

 chyma, and indeed in such a manner that the whole of 

 the connective tissue had a slightly yellowish brown hue 

 upon the surface, whilst in the deeper parts the deposi- 

 tion had only taken place in the fine elastic fibres of the 

 connective tissue, the intervening parts, the proper basis- 

 substance, being perfectly free. But deposits of an en- 

 tirely similar nature take place also in more remote 

 organs. Our collection contains a very rare preparation 

 from the kidneys of a person who on account of epilepsy 

 had long taken nitrate of silver internally. In it may be 

 seen the Malpighian bodies, in which the real secretion 

 takes place, a blackish blue colouring of the whole of the 

 membrane of the coils of the vessels, limited to this part 

 inHhe cortex, and appearing again, in a similar, though 

 less marked form, only in the intertubular stroma of the 

 medullary substance. In the whole kidney, therefore, 

 besides the parts which constitute the real seat of their 

 secretion, those only are altered which correspond to the 

 ultimate system of capillaries in the medullary substance 



