ORDERED TO WITTENBERG. 31 



dry there a few hours before putting it back in its 

 place. Strange to say I was not visibly wounded, only 

 the violent pressure of the air had so contused the 

 skin of my left hand, that the forefinger and thumb 

 were covered by a large haematocystis. Unfortunately, 

 however, the drum of my right ear was fractured, 

 which I immediately perceived from the circumstance 

 that I was able to blow out the air through both 

 ears: the drum of the left ear had been burst the 

 year before during artillery practice. I was in con- 

 sequence for the moment quite deaf and had heard 

 no sound, when suddenly the door of my room opened 

 and I saw the whole anteroom full of horror-stricken 

 people. The report had immediately spread that one 

 of the two officers resident in the lodgings had shot 

 himself. 



In consequence of this mishap I have long suffered 

 of difficulty of hearing and still suffer from time to 

 time, whenever the closed rents in the tympana chance 

 to open. 



In the autumn of 1840 I was transferred to Witten- 

 berg, where I had to enjoy for a year the dubious 

 pleasures of life in a small garrison -town. All the 

 more eagerly did I continue my scientific studies. In 

 that year Jacobi's discovery was made known in Ger- 

 many of precipitating copper in a metallic form by 

 means of the galvanic current from a solution of the 

 sulphate. This process interested me in a high degree, 

 as it evidently was the key to a whole class of hitherto 

 unknown phenomena. As I succeeded well with the 



