*the Microfcope explained . vii 
Make a round hole in the window fhutter, about 
4 and i-8th inches diameter ; to which apply the fquare 
plate A A, fig. 4. with the circular part D uppermoft, 
then mark the places of the two holes a a with a fmall 
black lead pencil, and bore them through the £hutter of 
a fize fufficient to let the mill’d headed fcrews B B pafs 
freely through them, which entering the holes a a, will 
hold the plate faft to the infide of the window fihutter; 
the looking-glafs C, being firft put through the hole, 
will remain on the outfide of the window, the iafh or 
cafement being firft thrown open. 
Screw the part b b of the Hiding tubes I K into the 
hole at H. Then prepare the microfcope fig. 5. for 
obfervation. Take out the tube I, and fcrew the tube 
M into the end N of the microfcope NP, and put the 
fhort Aider R that contains a convex lens, to increafe 
and enlarge the field of light, into the dove-tail plate 
gkh. 
Place the object which is fuppofed to be either in an 
ivory or on a glafs Aider, as E or F, between the thin 
plates c d and g h, then fcrew on one of the magni¬ 
fiers at the hole i. There are fix belonging to this tooth 
and pinion microfcope, and one of them is reprefented at 
Y. Or if the magnifiers are placed in a wheel as PQ_* 
turn it fo as to bring one of them under the center of 
the hole at i. Then darken the room as much as pof- 
fible, that no light may enter, but what pafies through 
the tubes I K. From this circumftance, and the bright- 
nefs of the fun-fhine, you are only to expeCt a per¬ 
fectly clear and diftinCt image. 
Now adjuft the looking-glafs C to the pofition of the 
fun, by turning the heads at e and f, the firft inclines 
the 
* Note, we prefer the ufe of the magnifiers fet in round 
buttons as reprefented at Y, inftead of being fet in a circular 
plate PP. 
