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CVI. An Account of Mr . Samuel TullV 
Method of cafirating Fifh . Communicated 
by W. Watfon, F. R. S. 
To the Royal Society . 
Gentlemen, 
Read Dee. 19, OEveral years fince, Mr. Tull of Ed- 
1754 monton performed the operation of 
caftrating fifties, before Sir Hans Sloane, Bart, and 
feveral members of the Royal Society, who met at 
Sir Hans’s houfe for that purpofe. About five or 
fix years ago he performed the fame operation in 
prefence of our late worthy Prefident Mr. Folkes, 
myfelf, and feveral others. Among thefe was a very 
valuable member of this Society, Mr. Trembley, 
who is with the Duke of Richmond on his travels, 
and is now at Feltzberg in Auftria, at a country-feat 
of the Prince of Lichtenftein. This nobleman, who 
is a great lover of natural hiftory, as well as a zeal- 
ous promoter of ufeful knowlege, is very curious in 
whatever relates to the hiftory of fifties ; and being 
informed by Mr. Trembley, that he had feen fifties 
caftrated in England, and of the advantages which 
he had been aftured did refult from it, his highnefs 
intreated him to procure him from hence the raoft 
exatt account of the manner of performing this ope- 
ration, and of feveral particulars relating thereto. 
M*. Trembley accordingly wrote me a letter, de- 
firing me, if poflible, to tranfmit to him this in- 
formation. In confequence of which, I wrote to Mr. 
2 Tull, 
