C 190 ] 
rectifying miftakes, and encouraging every branch of 
ufeful knowlege, I fhall think my time well em- 
ploy’d in this inquiry, which had its rife from your 
inftrudive convention. I am, with the higheft re- 
iped, 
S I R, 
London, April 15, Your mod: obedient, and 
1 753 • • ^ 
mod: humble fervant, 
John Rond. 
XXIX. A Letter from Dr. Bevis to Mr. 
James Short, F. R. S. concerning Mr. Gaf- 
coigne’j Inventmi of the Micrometer. 
Dear Sir, 
Read May 17, A L THOUGH Mr. Townley, in 
I753 ‘ /a his letter to Dr. Croon, printed in 
the Philofophical TranJ< aft ions, N° 25, p.457, has 
fufficiently made appear, that the invention of the 
micrometer was Mr. Gafcoigne s, and that he applied 
it to meafuring fmall angles in the heavens, and for 
fettling the moon’s parallax, long before Meffieurs 
Auzout and Picard thought of any fuch matters ; yet 
are the French aftronomers at every turn for giving 
it to thefe their countrymen, without fo much as 
once mentioning the name of Mr. Gafcoigne. 
No fooner had the late Dr. Derham reftor'd the 
application of telefcopic fights to quadrants to its true 
author Mr. Gafcoigne, than M. de la Hire, who never 
made the dodor any reply on that head, took occa- 
fion, 
