From Horace Darwin to G. H. Darwin [February–June 1881?]

Dear George

I enclose my comments. I have done nothing more to the pendulum since I came back, & I am afraid I shall not be able to spare any time to it, the shop takes all my strength & I wish I could give more time to it. But I hope to catch up the arrears of work soon, but there is plenty to do just now. When I left you at Peterborough I had an hour to spare at the Cathedral, & I saw there that the eleventh Abbot (in 1055) of the monastry wh. stood there was called Arwinus, most probably our great uncle. The D, would be put on by the Normans & the “us” is latinizing it I suppose. Claudie & Noel are here. F.M.B has asked Clau & me to Hall, & Clau is much frightened & expects to find all the dons over 80.

To return to the Pend. & the forces on the swinging piece of glass between the electrodes. The force on it (if it existed) would do no harm if the current was turned on say every minute for an instant, & the difference of the current for that instant through each of the two electrodes would move a relay. The viscosity of the liquid would prevent the glass moving for the instant as you suggested. This to me looks a v. hopeful plan. The instantaneous current wd. make electrolysis less hurtful too. How lovely lighting your house by wind. Im v. sorry your cold is obstinate

Yours H Darwin