i 3 o HERMANN VON HELMHOLTZ 



effects : she had suffered from a cough since the birth of her 

 children, and did not spare herself enough in her invincible 

 loyalty to her duties. The doctors thought that the cold 

 climate of Konigsberg was one cause of her frequent illnesses, 

 and when the physiological post in Bonn fell vacant, Helmholtz 

 naturally endeavoured, if only in his wife's interests, to get 

 himself transferred from Konigsberg. 



He took no steps, however, without ascertaining the wishes 

 of his old friends Ludwig and du Bois-Reymond, in case the 

 former wished to return to Germany, and the latter to become 

 a regular professor at last. It was not until he heard that 

 Ludwig's political attitude at Marburg, and the erroneous 

 reports as to his atheism, gave him no prospect of a call to 

 Prussia, and that du Bois hesitated to take this post because 

 his appointment to the chair at Berlin was almost a certainty, 

 that he wrote on November 5, 1854, from K5nigsberg to du 

 Bois-Reymond : 



' If you have decided not to take the vacant post at 

 Bonn, I should be obliged if you would let me hear definitely, 

 because at an equivalent salary I should prefer the post at 

 Bonn, and should like to approach the Ministry on the subject. 

 My reasons are that I should have a wider circle of activity at 

 Bonn, a slight though not at first important increase in fees, 

 and, lastly, there is my wife's health, which seems to be 

 seriously endangered in this climate. I myself lose no small 

 portion of my energies for work through the inevitable chills. 

 You see that my reasons are not so pressing as to prevent my 

 leaving the post to you with the best possible grace, but I 

 should grudge it to any one else/ 



Du Bois did not reply till December 6, when he writes : 

 ' I was unable to send a definite answer to your letter before, 

 and cannot do so even now. Strictly speaking, I have never 



approached the subject of Bonn with the Ministry With the 



name you have made for yourself as a teacher you cannot 

 fail to get another appointment before long. I shall probably 

 keep out of the running. At present it makes me furious to 

 see my neglected apparatus and manuscripts, and how you 

 managed in your first years at Konigsberg to make such 

 colossal researches is a mystery to me. But, to be sure, Du 

 gleichst dem Geist, den Du begreifst? 



