3 2 The Magnifying Power of Glajfes • 
and induce many People to be fond of thli 
mod delightful and inftrudive Study, when 
the Difficulties they imagined in it are re~ 
moved, and they perceive it to be as eafy as 
it is pleafant ; when they find themfelves 
able to judge of what they fee, not by mere 
random Guefs, but by certain and plain 
Principles. 
C H A P. VIII. 
To find the Magnifying Power of Glajfes em¬ 
ployed in Single Micro/copes . 
T HE'Appearance of anyObjed, as to 
Magnitude, is according to the Angle 
it is feen under ; or, in other Words, ac¬ 
cording to the Nearnefs it can be brought 
to the Eye : for the lefs the Diftance it can 
be viewed at is, the more it will appear en¬ 
larged. 
The naked Eye is unable to diftinguiffa 
any Objed brought exceedingly near it: but 
looking through a convex Lens, however 
near the Focus of that Lens he, there an 
Obied maybe difMndtyfeen: and the (mailer 
the Lens is, the nearer will be its hocus, 
and in the fame Proportion the greater muft 
he its magnifying Power, 
From 
