From Horace Darwin to G. H. Darwin 6 March 1876

Dear George

I have been meaning to write to you to tell you what Maxwell said about, the modification of my dynamometer as applied to finding Joule’s equivalent. I went to see him when I was at Cam. & he was very jolly, & told me a lot of dogey things. I explained my plan to him, & he said he thought it was better than any tooth gear arrangement, & even said something of that nature twice, I think that this is very satisfactory, as I believe that his plan had tooth wheels in it, and also that it is so very hard to get an opinion ought of him. I shod. not be surprised if he used something of the sort. How are you getting on in the pitch machine? I am in the drawing office now so that when you want it done I could very easily do it up there, & get it done quickly I hope. When I have done my present job I shall do the spanners and after that, I hope I shall make a working drawing of the dynamometer, & I shall be very much pleased if they make it, I think there is some chance of it. I’m working at the planetary motion too now and have got the worst of the drawing done. & then I shall take it to the man F Galton recommended. It will not be a very clumsey thing when done, planet 80^lbs. & the whole thing standing 7^ft. high. about. & greatest distance of the planet from sun 2^ft.3″. I suppose you will be coming home soon.

Yours | H Darwin | Love to Pouter