12 Wilson's Single Pocket Microfcope . 
the Claw of a Flea, the Horn of a Loufe, or 
the like ; yet by gently moving the Slider 
that contains your Objed, the Eye will 
gradually overlook it all : and if any Part 
lliould be out of Didance, the Screw CC 
will eafiiy bring it to the true Focus. 
As Objeds muft be brought very near the 
Glaffes when the greateft Magnifiers are 
ufed, be particularly careful not to fcratch 
them by rubbing the Slider againd them 
as you move it in or out. A few Turns of 
the Screw* CC will eafiiy prevent this MiG 
chief, by giving them Room enough. 
You may change the Objeds in your 
Sliders, for what others you think proper, 
by taking cut the Brafs Rings with the 
Point of aPen-knife; thelfinglafs will then 
fall out, if you but turn the Sliders ; and 
after puttingwdiat you pleafe between them, 
by replacing the Brafs Rings, you will 
fallen them as they were before. *Tis pro¬ 
per to have fome Sliders furnifhed with 
Talcs, but without any Objeds between 
them, to be always in Readinefs for the 
Examination of Fluids, Salts, Sands, Pow¬ 
ders, the Farina of Flowers', or any other 
cafual Objeds of fuch fort as need only be 
applied to the Outfide of the Talc. 
The Circulation of the Blood may eafiefl 
be Teen in the Tails or Fins of Filhes, in the 
fine Membranes between a Frog’s-Toes, or, 
beR of all, in the Tail of a Water-Newt. 
If 
