36 SOME AMERICAN MEDICAL BOTANISTS 



from Kew, 1759, written for the Philosophical 

 Transactions, entitled, A Letter Concerning the 

 Force of Electrical Cohesion. 



Linnaeus named the familiar and beautiful 

 little checkerberry, Mitchella repens, after him, 

 and kept up a constant and affectionate inter- 

 change of letters. The last of those from Mit- 

 chell are dated 1751, one to Linnaeus, one to Bar- 

 tram, and this date would make one conclude that 

 he never returned to America, as no letters seem 

 extant after 1751 from the new country. To Bar- 

 tram he says : 



" I have had so much business of that kind 

 (writing) upon my hands since I came to Eng- 

 land, that I have contracted a disorder by it, 

 which makes me unable to pursue it any longer 

 or even to sit down to write a letter, especially one 

 that requires any thought, without being sensibly 

 the worse for it." He died in March, 1768, 

 though where I cannot discover. 



There is some more of his work which ought to 

 be mentioned, notably, A Map of the British and 

 French Dominions in North America, London, 

 1755, which is said to " mark an era in the geog- 

 raphy of North America," and was quoted in 

 boundary negotiations. A French copy was pub- 

 lished at Paris, 1756, and a second English edition 

 appeared in 1757; reprinted, 1782; the British 

 Museum is the fortunate holder of copies. His 



