XXV11I 
The Microfcope explained. 
your objedt ; and put the concave fpeculum S on to the 
outfide of the ring R, you will find in the body of the 
microfcope, between the wood or brafs F, and the end 
of the male fcrew CC, a fmall hole U, through which 
Hide the long wire T, which has a point at one end, 
and forceps at the other, that may be ufed occafionaliy, 
as your objedt requires : when you have fixed this, and 
your object on it, turn the arm R, which is performed 
by two motions, till the magnifier is brought over the 
©bjedl; it may be then adjufted to the true focus, by 
turning the male fcrew C C, in the fame manner as 
before defcribed. It mult alfo be turned exactly over 
the fpeculum, by twilling the upper part of the fcrole to 
one fide, till your objedt, and the two fpeculums, are 
in one line, as will be found by trial, and then fix it 
by the fcrew B, at which time the upper furface of the 
objedt will be fo exceedingly enlightened by the light 
refledted upward from the mirror, to the concave fpe¬ 
culum, as to be feen as clear and diftindt as any tranf* 
parent one. 
The manner of applying Wilfon’s pocket mi¬ 
crofcope to the folar apparatus. 
HE folar apparatus having been already defcribed. 
JL it remains only to fhew how Mr. Wilfon’s pocket 
microfcope is to be applied to it. 
After having fixed the apparatus to the window-fhut- 
ter, and adjufted it to the altitude and fituation of the 
fun, fo as to form a round fpot of light on the fcr-een. 
Screw the tube K, fig. 4. into the middle of the plate 
A A at H, taking care not to alter the looking-glafs, 
after it has been adjufted to form a round fpot of light 
as directed before in the ufe of the folar microfcope \ 
then fcrewing the magnifier you choofe to employ to the 
end 
