222 Edward Livingston Youmans. 



this, together with some other matters of interest, is 

 given in the following letters to his sister : 



LONDON, July 21, 1866. 



There are but few boarders here at Mrs. Langford's, 

 which makes it pleasant, and I have a separate room with 

 all my books and papers, which is very convenient for study. 

 The situation is high, and up near Regent's Park and very 

 eligible, so I shall be contented here a while. I have been 

 thus far reading and making references, and am just now 

 beginning to write. The subject opens finely before me, 

 and I hope I shall have grace to do it justice. Spencer 

 has promised to look over my argument when I get it 

 ready. ... I had almost forgotten to say that Wislicenus 

 and Fick (the latter a physiologist of Zurich) have given 

 the last annihilating blow to Liebig. Their joint paper 

 has been translated, and published in the Philosophical 

 Journal, a copy of which, with Spencer's last number, I 

 have left at Layton's to be sent to New York and forwarded 

 to you by post. It will leave here the last of next week. 

 I am going to write to Wislicenus, asking him the privilege 

 of making a sketch of his American experience preliminary 

 to his statement of his researches, for publication at home. 

 He has proved that animal power is due to the combustion 

 of the hydrocarbons in the muscles, the heat produced 

 being converted into mechanical force ! 



LONDON, September /, 1866. 



We got here yesterday afternoon, and your letter of 

 August i4th came in the evening. I was greatly rejoiced 

 to learn that you had all gone a-fishing; I hope you will 

 follow it up. The only way to strengthen any tendency, 

 faculty, or habit, is through its own exercise. You can't 

 infer its propriety and then enter upon it. It is a great 

 " victory over the inane " to learn to fish. Pray go often. 

 I shall when I return. I am hard at work, pushed and 



