208103on PERSPECTIVE.
Mirrours muſt not be plac’d within the Machine;
for
in ſuch a cloſe Place, ones Breath will ſully them; but
not the Convex Glaſs, becauſe it is encloſed in a
Tube.
72[Figure 72]in ſuch a cloſe Place, ones Breath will ſully them; but
not the Convex Glaſs, becauſe it is encloſed in a
Tube.
The Figures repreſented in the Camera Obſcura
are form’d (as is demonſtrated in Dioptricks)
by Rays which coming from all the Points of the
Objects, paſs through the Centre of the Glaſs:
So that an Eye placed in the ſaid Centre, would
perceive the Objects by the ſaid Rays, which
conſequently by their Interſection with a Plane,
muſt give the true Repreſentation of the Objects.
But the Pyramid which the ſaid Rays forms
are form’d (as is demonſtrated in Dioptricks)
by Rays which coming from all the Points of the
Objects, paſs through the Centre of the Glaſs:
So that an Eye placed in the ſaid Centre, would
perceive the Objects by the ſaid Rays, which
conſequently by their Interſection with a Plane,
muſt give the true Repreſentation of the Objects.
But the Pyramid which the ſaid Rays forms