make any thing of the matter. And it is probably,
from this very groupe, that Albani, who ftudied
Raphael fo clofely, drew the following precept of
his ; 64 That it behoves a painter to exprefs more cir-
curnftances than one by every attitude ; and fo t6
employ his figures, that, by barely feeing what
they are a&ually about, one may be able to guefs,
both what they have been already doing, and are
next going to do.'' This I know to be a difficult
precept ; but I know too, that it is only by a due
obfervance of it, the eye and the mind can be made
to hang in fufpence on a painted piece of canvas.
It is expreffion, that a painter, ambitious to foar in
his profeffion, muft, above all things, labour to per-
fect himfelf in. It is the laft goal of his art, as So-
crates proves to Parrhafius. It is in expreffion that
dumb poetry connfts, and what the prince of our
poets calls a vifible language.
pERSPECTIVE is the art of delineating vifible
objects on a plain furface, fuch as they appear at a
given diftance or height, upon a tranfparent plane,
placed perpendicular to the horizon, between the eye
and the ohjecb.
There are three forts of perfpecbive, viz. linear,
aerial, and fpecular perfpeclive.
Linear perfpeftive (to which moft properly belongs
our definition, and which is a branch of the mathema-
tics'; regards the pofition, magnitude, form, &c. of
D 2 the