Con'('«jton(f<'urt' icifh ('Itnrlin Durti'iii MM 



i lio|i(< I li»vt> nii.Hworixl fully ciiougli, and much rt^rt't tliut 1 iiiiHUixifrMtotKi liic i|Ui'>tiMii, 

 as put ill your Father's lettor, mid have j{iv<>ii you both iiiiiifcfs«j»ry trouhlf. I am t-iini-r to 

 reaeivo criticiHiiis — i-ven ailveisi- ones. Kvi>r yours, Fhancis (Jai.ton. 



About your Father's plants and tlin statistics of j;rowtli: — In ciifK's where not only the onf. 

 biggest of each sort, but the two or three biggest were measured, the uncertainty of the relative 

 values of the moduli of variability of the tw(f sorts would l)e materially diminished. 



42 Rutland Gatk, London. Jnn. 30th, 1876. 



My DKAii Oeoiujk, 1 was very glad to hear good news of you fniin Litclitield, who dined 

 with us a few (lays back ; (but not with your sister, I am sorry to say, as she was not then well). 

 Strachey was nearly going yesterday to look after your map frame, possibly he did after all 

 (he asked ine to join liim but I was engaged). He thought of taking it IxKlily away. Never 

 did a thing hang so long in hand as this, but I am powerless to help. I can't understand it, as 

 iStrachey is so energetic iu much that he undertakes and does it so well. 



I got a letter fn)m tJlaisher a short time bick alH>ut my "exjwnential ogive'' whereof he 

 much approves, name and all, and he gives me a compact expression for it, in t<!rms of his "error 

 function." I enclose a copy of part of what he says. In working out your Father's plant sta- 

 tistics, it occurrwl to me that it would bo uncommonly convenient to calculate an exponential 

 ogive tjible, which I did, and since receiving (JIai.sher's letter I sent it to him to see if he could 

 get it projierly recalculatwl for me directly from his formula. You see, — by knowing any two 

 ordinate.s, you knowtlie whole curve and can at once get the value of any other ordinatos in it. 

 I need not bother you with particulars about the table, further than that it gives ordinates from 

 1 to 50 in an ogive of 100 places, from 1 to 50 in an ogive of 1,000 places, ditto 10,000, 

 100,000 and a million. So that nil goes into a |>age. 



But I could not make out anything by its means about those data concerning your Father's 

 self- and crop-fertilised plants in which only the biggest were measured. Their "run" was too 

 irregular. I could get no two trustworthy ordinates. The ignorance of the number of plants in 

 the row did not so much matter, becau.sc one knew it within limits and could find what the 

 result would be for those limits; l>et\veen which the real result must lie, and these were not 

 extravagantly far apart. 



AVe have had astoiii.shing fogs in this part of Ivondon, that is going up from here to Hyde 

 Park corner. I never .saw one thicker than yesterday. Your friend t'ookson, whom I met 

 walking this morning, told nie that in one place he could only see three flagstones off. I sup- 

 pose you have glorious sunshine in Malta. 



Tyndall's lecture al>out Bacteria was a great success and seems to have utterly smashed the 

 adherents of Bastian. T conclude from the theory that the physiological reason of immortality 

 in the next life is that there are no Bacteria in the pure air of heaven! — nothing to cause 

 corruption. 



I send reprint..s of my twins and theory of heredity (revised); one of the twin imijh'i-s is 

 new and so is the last paragraph alxxit the ruckoo in the one that was in Fraser, which if yoa 

 care to li>ok at may interest you. Koiuanes' paper has l)cen selected as the Croonian I>>cture 

 of the Koyal S<Kiety for the year; a well-<leserved honour. There seems to be an epidemic in 

 the learned societies. Not only the Linnean, but now the Anthropological has got into such a 

 stat*>, and the rtwpectable Athenaeum is all in a boggle about its future trustee to replace 

 Ix)rd Stanhojie. Pniy remember me very kindly to your brother and with my wife's l)e8t 

 regards. Ever yours, Francis Galton. 

 (Jkohok Dakwin, E.s(|. 



2, Bhvanston St. [1877] 



.Mv DKAU G[ai,ton]. 1 have just U'thought me, that I received a French essay a few months 



ago on the efFect-s of the conscription on the height of the men of France and on their liability 



to various diseases which reiulerod them unfit for the army, due to the weaker men left at home 



prowigatiiig the race. Ho shows, I think rightly, that no one hitherto had considered the 



I problem in the proper light. I forgot author's name, — and where published. 



Do you know this es.sayt and would you care to see it. I suppose that I could find it, but 

 I think I have not yet catalogued it. It seemed to me a striking es.say. 



Ever yours sincerely, Ch. Darwin. 



