Letter from D'Arcy W [Wentworth] Thompson, University College, Dundee, to [Joseph Larmor] He sends Miss [Isabella] Leitch's data of the rate of growth of pea rootlets set against Thompson's calculated Van't Hoff curve. It is not a good fit, but if the law is not Van't Hoff's, it is close to it. The curve concludes remarkably well at the range of ordinary growing temperatures and he suspects the presence of some new interference factor at low temperatures. 21 March 1916