20th April, 1956.
Dear Miss Franklin,
I am enclosing samples of the cowpea strain of tobacco mosaic virus, one prepared from infected tobacco plants and the other from infected French bean.  These are all that I have at the moment, but I imagine and hope they will be enough for your purpose.  I should expect the one from tobacco to be like the type strain of tobacco mosaic virus but the other may well differ for in many of its properties it resembles Wildman's U2 strain.  Anyway I shall be interested to know what you get.
I am sorry that we do not have any purified preparations of potato virus X, but if we do make any I will see that samples go to you.
Yours sincerely,
F. C. Bawden