C 5*8 3 
to Perfection by Mr. Cuff s whofe Copper-plate and 
Defcription of it, as it will fave much Trouble, and 
make me better underftood, I take the Liberty, at his 
Defire, to prefent herewith, together with his printed 
Account of the Solar Microfcope, the Pocket Mi- 
crofcope, and the Microfcope before fpoken of, with 
a Scroll, Pedeftal, and Speculum, of which there are 
alfo Copper Plates. Thefe, with the large double 
reflecting Microfcope, are, I think, the chief, if not 
the only ufeful Sorts now made in England. 
I muft not omit taking notice, that Mr. Leeuwen- 
hoek fays, (in his Second Volume, Part II. pag. 93.) 
that fometimes, to throw a greater Light upon his 
Objects, he ufed a fmall convex Metal Speculum. 
How he applied it, I will not pretend to guefsj but 
it is highly probable our double reflecting Microfcope 
may be owing to this Hint. I mult alfo obferve 
farther, that in the Fourth Volume of his Works, 
pag. 182. after deferibing his Apparatus for viewing 
Eels in glafs Tubes, Mr. Leeuwenhoek adds, that he 
had another Inftrument, whereto he ferewed a Mi- 
crofcope fet in Brafs; upon which Microfcope, he 
tells us, he fattened a little Di(h (of Brafs alfo, I 
fuppofe), that his Eye might be thereby aflifted to 
fee Objects better : For he fays, he had filed the Brafs 
which was round his Microfcope, as bright as he 
could, that the Light, while he was viewing Objects, 
might be reflected from it as much as poffible. 
This Microfcope, with its Difh, (which I give an exaCt 
Copy of from the Picture in his Works) feems fo 
like our opake Microfcope with its filver Speculum, 
that, after confidering his own Words, I fubmit to 
your better Judgment, whether he is not properly 
