Eugenics as a Creed and the Last Decade of Galton's Life 393
Now r is very close to •5-it varies from about •46 to -52 for the best series in man. Weldon's results for mice not yet published give almost the same values. But he has so selected his pairs of mice that p runs up to -8! For man p may be safely put •2. Thus the ratio you want
is = 1 = about •4.
The ratio of mean filial deviation to parental deviation, i.e. for a single parent, is •5 but of course the prediction in this case is subject to a larger probable error; these errors in the two cases being about in the ratio of 1/•75 to %/-60, the latter corresponding to the midparental
I hope this will not be too complex, and that I have given what you want. Pray write again if there be any further point I could make clearer.
I had a letter from the Principal of the University saying that the University was drawing up a list of their needs and asking me to say what the Galton Eugenics Laboratory needed. It was a somewhat difficult question to answer since if the University is in the way of getting money, there is no reason why the Laboratory should not have a considerable share. I suggested that £100 a year for books, £200 for publications, and £500 to pay a man to give the bulk of his time to supervision, could be easily assimilated ! If we get 4 of all this from the University we may be happy, but it really is a sign of the times that they ask us if they can aid. We are very full this session. In the Biometric and Eugenics Laboratories together we have I think 16 research workers, and practically no vacant tables.
I shall shortly send you the average numbers of certain classes of relatives-aunts and uncles. I fear we cannot work cousins because the records are too incomplete.
Has Wee Ling behaved himself, or has he become a nuisance? Don't hesitate to return him if he has become a difficulty.
THE RECTORY, HASLEMERE. October 25, 1909.
MY DEAR KARL PEARSON, You can with difficulty understand how incompetent I am to do mental work. I have blundered much in putting the enclosed into shape, desiring to avoid needless complexity, and now if the suggestion (B) be adopted the problem becomes apparently simple enough. Still I dare not trust myself to do it. I only want a rude approximation, but want one very much.
Nettleship lunched with us on Saturday and inspected Wee Ling's eyes. The puppy is a joyful little beast with a now tightly curled tail and is a friend with all the servants. But he has a horrid temper, and bites with his little sharp teeth and swears in Chinese dog -language, a quite different language to that of English pups. He had a sharp lesson from the cat, in social usages ; for trying to oust her from her chair, he received a wipe from her claws across his little pink nose. No real harm done, but it must have hurt.
We are well placed and the air of Haslemere suits me perfectly, but I do very little. Sir Archibald Geikie tells me of scientific events. He was delighted with Birmingham and remarked that among the men selected for degrees were two brothers (Haldane), one brother and sister and brother-in-law (Balfour, Mrs Sidgwick and Lord Rayleigh).
I asked Nettleship about you, whether he thought you were not working too hard. He evidently thought so, but added that you were like a racehorse, difficult to keep quiet. And here am I bothering you about a problem ! How I wish you could be relieved from routine work. I wonder if you will come down to see your friends hereabouts?
My niece is happy, after 21 weeks out of the allotted 4 weeks in bed, for rest-cure. She hopes to get abroad to S. France in early winter, leaving me in charge of another niece (Mrs Lethbridge). I am fortunately well-meted; three are at the moment hereabouts, two in this house and one hard by. Ever affectionately yours, FRANCIS GALTON.
This letter contained the following problem of which a solution was sent to Francis Galton as a New Year's Greeting, 1910, and was published in Biometrika, Vol. X, pp. 258-275.
Affectionately yours, KARL PEARSON.
P G III