166 Life and Letters of Francis Galton
work, otherwise it is hard to understand why the further work was carried out, especially why in association with Darwin, who had denied its bearing on Pangenesis.
There was evidently a good deal of correspondence, now sadly missingwhich would have explained Darwin's views on these renewed experimentsduring the summer of 1871. We shall now put before the reader the remainder of this somewhat fragmentary correspondence, using it as a frame for Galton's earlier work on heredity, which we shall discuss as it is referred to. Some few of the letters of Galton have been printed in the preceding chapter ; others are omitted as merely referring to the arrangement of meetings in London or at Down.
(14) We are now in Yorkshire. (Address) 42, RUTLAND GATE, LONDON, Sept. 13/71.
MY DEAR DARWIN, I had proposed writing to you, in a few days' time, about the rabbits when I received your letter. First, let me thank you very much for the kind care you have taken of them. Secondly---I grieve to hear from you, that your holiday has not been so much of a success as you had hoped so far as health is concerned and, thirdly on my own part, I am glad to say, I am and have been particularly well (except only a boil inside the ear, which hurt badly for a few days).
To return to the rabbits:-Will you kindly prevent the bucks having any further access to the does, and make away with all the young except, say, 4 or 5 as a reserve in case of continued accident in the forthcoming series of operations. As soon as I return to town, towards the end of October, I will ask you to send me the old rabbits, and will begin at once to cross-circulate every one of them. My present assistant (a most accomplished young M. B. in medical science) has not the manipulative skill of my old friend and I fear I shall have an undue proportion of corpses, but there must be some successes out of the 3 does and 3 bucks that you have and the other 3 that I have.
Latterly, my whole heart has been in rats; white, old English black, and wild grey, which I have had Siamesed together in pairs, chiefly white and wild grey (for my stock of black is low), in a large number of cases-perhaps 30 or 40 pair. These have been fairly successful operations so far as the well-being and comfort of the animals is concerned, but unexpected, out-of-the-way accidents, are continually occurring. One pair died after 63 (about) days of [union] and injection into the body of the one passed into the other. I hope in this way to test Pangenesis better than by the cross-circulation for if even 1 drop of blood per hour passes from rat to rat, a volume equal to the entire contents of the circulation of either will be interchanged in 10 days, and this is equal in its effects to a pretty complete intermingling of the bloods. All crystalloids diffuse readily from rat to rat (as poisons) through the tissues, and as we know that eggs of entozoa are carried through the veins by the blood, it seems that a long continued Siamese union would be a valuable means of experiment.
We look forward with much pleasure to our return to town, to see your daughter in her new house. I do not think that I wrote myself, for my wife was writing to offer you, which I do now, my heartiest congratulations on the event. But, you must miss her.
Ever sincerely yours, FRANCIs GALTON.
(15) 42, RUTLAND GATE, S. W. Nov. 9/71.
MY DEAR DARWIN, I had not the least doubt but that I could have sent you before now definite results about my rabbits, but I cannot:-you must have patience with me and wait yet longer. The cold has killed one litter to which I had looked forward, and I have had a series of other mishaps not worth specifying, the result of which is that I have only one silver grey litter to go by-viz :-that of which I told you, which included a yellow one, slate grey on the belly, with some white on his tail. I should have thought this a great success but it may be pronounced a 'yellow smut'! Another result is that I have built a good serviceable little house for the rabbits in my own backyard and have all the best of them under my own eye, now. The litter that died from cold, looked very hopefully marked-but I think one cannot trust to,