196.
The Uſe of the
Camera
Obscura
in Deſigning.
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.
EVery one knows how eaſy it is by one Convex Glaſs
only, to repreſent outward Objects in any darken’d
Place, according to their natural Appearances, where
the Livelineſs of Colours, and the Diverſity of Mo-
tions, are wonderfully pleaſant to behold; and it is
ſo eaſy to make this Invention uſeful in Deſigning,
that our treating of it ſo fully as we have done, is
undoubtedly ſomething neceſſary.
A few Hints and Obſervations ſeem to be ſufficient
for putting a diligent Perſon in the way of contriving
himſelf ſome Machine to perform the Uſes hereafter
mentioned; whence we might have let him bad the
Pleaſure of the Invention himſelf, after it was made
eaſy to him. And this indeed is what I firſt reſolv’d
upon; but afterwards conſidering that in the Con-
ſtruction of a Machine for facilitating the Buſineſs of
Deſigning, ſeveral Things cannot be foreknown till
try’d; and that much Time may be ſpent in vain, and
ſeveral Methods attempted, before one of theſe Ma-
chines can be made ſimple and uſeful, as I have found
by Experierce: Therefore, that others may not be at
this Trouble, I ſhall here lay down the Deſcription of
two Machines (hoping it will not be unacceptable)
which after ſeveral Alterations, in my Opinion, are
now made convenient enough.