1792.] TO HUMPHRY MARSHALL. 



you for a few leaves of it, and also a few seeds, with the 1 k. 



when it is returned. 



I cannot omit mentioning, that a patient in the Edinburgh In- 

 firmary, who took the medicine as directed by J>r. Withering^ 

 vomited to death. This determined me to avoid the medicine ; but 

 dropsies are so often fatal, that we must try everything. 



I am, with great respect, 



Your assured friend, 



Caspab Wistab, -Ik. 



October 21st, 1787. 



[In the year 1792, the American Philosophical Society (of 

 which Humphry Marshall was a memher) appointed a commit! 

 consisting of Thomas Jefferson, Benjamin Smith Babti 

 James Hutchinson, and Caspar Wistab, "for the purpose of 

 collecting and communicating to the Society materials for forming 

 the Natural History of the Insect called the Hessian Fly, as also 

 information of the best means of preventing or destroying the 

 Insect, and whatever else relative to the same may be interesting 

 to Agriculture." That committee prepared a circular, containing 

 a number of queries relative to the insect, and its habits; and a 

 copy was sent to H. Marshall, accompanied by the follow' _ 

 note, from Dr. Wistar.] 



Respected Friend : 



I trust the importance of the subject will be a sufficient apology 

 for the trouble I am about to give thee. 



The Society was induced to undertake the inquiry respecting 

 the Hessian Fly, by the hope of ascertaining some method of 

 avoiding its ravages, as well as by a wish to establish the fact, that 

 it is not carried with the grains; an apprehension of which I 

 been injurious to the sale of our wheat in Europe. 



Any observations thee may have made, or can collect, will be 

 gratefully received by the committee, and will particularly oblige 



Thy respectful friend, 



Caspar Wistab, Jr. 



May 27th, 1792. 



P. S. Has Dr. Marshall any inclination to explore the country 

 west of the Mississippi ? If so, I shall be very glad to see him 

 when he comes to town. 



