ng, and made in the shape of a truncated pyramid, whose base, B
D F G, is eight inches wide, and six inches high. Fix to the other end
of it a tube of four or five inches long, and which you can draw out
from the box more or less. Line the inside of the box with black
paper, and place it on a leg or stand of wood, H, and on which it may
be elevated or depressed by the hinge I.

Take a small frame of wood, and divide it at every inch by lines of
black silk drawn across it, forming forty-eight equal parts; divide
these into still smaller equal parts, by lines of finer silk:[C] fix
this frame at the end of B D, as the base of the pyramid.

Provide a drawing-paper, divided into the same number of parts as in
the frame, by lines, lightly drawn in pencil. It is not material of
what size these divisions are; that will depend entirely on the size
you propose to draw the objects by this instrument.

Place this instrument opposite a landscape, or any other object that
you want to draw, and fix the leg firmly on, or in the ground, that it
may not shake; then turning it to the side you choose, raise or
incline it, and put the tube further in or out, till you have gained
an advantageous view of the object you intend to draw.

Place your eye, E, by the instrument, which you have adjusted to the
height of your eye, and, looking through the tube, carefully observe
all that is contained in each division of the frame, and transpose it
to the corresponding division in your paper; and if you have the least
knowledge in painting or even drawing, you will make a very pleasing
picture, and one in which all the objects will appear in the most
exact proportion.

By the same method you may draw all sorts of objects, as architecture,
views, &c., and even human figures, if they remain some time in the
same attitude, and are at a proper distance from the instrument.

[C] The different thicknesses of the silk serve to
distinguish more readily the corresponding divisions.

_Illuminated Prospects._

Provide yourself with some of those prints that are commonly used in
optical machines, printed on very thin white paper; taking care to
make choice of such as have the greatest effect from the manner in
which the objects are placed in perspective. Place one of these on the
borders of a frame, and paint it carefully with the most lively
colours, making use of none that are terrestrial. Observe to retouch
those parts several times where th