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I entreat you will prefent my relpedls to the Royal 
Society j and that you will believe me to be,- with 
great truth and efteem, 
Dear Sir, 
Your moft obedient 
humble fervant, 
F.. H. Eyies Stiles,. 
^'T^HESE glalTes are fo fmall, that the diameter 
of the higheft magnifier among them is but 
half a Paris point, which is, if I miftake not, no 
more than of an inch, the point being of a 
line, and the line of an inch. 
The great difficulty, with refped to thefe glafies, 
confifts, as Padre di Torre tells me, in- the handling 
them, and the getting them into the little brafs foc- 
kets, prepared for their reception. The making 
them in his method is foon done ; but they mufi be 
focketed before he can examine to fee whether the 
fiame of his lamp, which produces them, -has fuc- 
ceeded to the perfedion he wiflied j that is, whdher 
they be perfedly fpherical, and without flaw, fpeck, or 
other accident, which they, are fo liable to, that he 
makes many, before he produces one to his mind : and 
indeed he lets fo little value upon them, till he has 
proved them by the vifion of fome objed, that if one 
of them, when he has made it, flips out of his little 
pincers before it has been proved, if he cannot re- 
cover 
