To George Howard Darwin 
Can you or any of your friends answer me this.1 In a family of 10 5 of the children squinted & 5 did not & they came alternately—.2 But you must understand it is indifferent whether a squinter or a non squinter comes first. What I want to know is what are the chances against their coming alternately.3
Yours affec | Ch. Darwin | Ch. Darwin | Ch. Darwin4
P.S This case of the squinting & other such cases are real.
Asks GHD what the chances are against squinting and non-squinting children coming alternately in a family of ten.
Please cite as
Darwin Correspondence Project, “Letter no. 4961,” accessed on 11 February 2016, http://www.darwinproject.ac.uk/DCP-LETT-4961