224119on PERSPECTIVE.
46.
When we have a mind to remove this
Machine from one place to another, we lay the
Box B E C upon the croſs Pieces 2, 3, 4, 5, with
its opening A B C upwards; then we put the
little Box Y, the Ruler and Mirrour (mentioned
Numb. 13.) the black Cloth, and the two Sticks
M L and I H, all into the ſaid great Box; and
afterwards partly cover it by the Frame G, 1140. which is ſuſtained by two very thin Rulers, and
then by another little Board, when the Frame is
not big enough. The whole Machine thus taken
to pieces, will take up no more room than the
Support itſelf doth: and ſo it is very eaſy to re-
move from Place to Place. Now when Objects
are to be repreſented in this Machine, it muſt be
put together again, as per Figure; and the black
Cloth, for a Perſon to put his Head under, hang-
ing upon the Sticks, and faſtned to the Sides of
the opening A B, A C, and C D.
Machine from one place to another, we lay the
Box B E C upon the croſs Pieces 2, 3, 4, 5, with
its opening A B C upwards; then we put the
little Box Y, the Ruler and Mirrour (mentioned
Numb. 13.) the black Cloth, and the two Sticks
M L and I H, all into the ſaid great Box; and
afterwards partly cover it by the Frame G, 1140. which is ſuſtained by two very thin Rulers, and
then by another little Board, when the Frame is
not big enough. The whole Machine thus taken
to pieces, will take up no more room than the
Support itſelf doth: and ſo it is very eaſy to re-
move from Place to Place. Now when Objects
are to be repreſented in this Machine, it muſt be
put together again, as per Figure; and the black
Cloth, for a Perſon to put his Head under, hang-
ing upon the Sticks, and faſtned to the Sides of
the opening A B, A C, and C D.
The Uſe of this Machine.
47.
The Uſe of this Second Machine is the
fame as that of the Firſt; but it ought to be ob-
ſerved, that when we incline the Machine, 2243. Angle of Inclination of the Mirrour and Hori-
zon muſt be made leſs, by half the Inclination of
the Bottom of the Box; and when the Machine
is ſomewhat inclin’d backwards, the ſaid 3344. muſt be made greater by a like half. You muſt
likewiſe obſerve, that when Objects are to be
repreſented for a perpendicular Picture, the Ma-
chine muſt be placed according to the former
Part of Numb. 44. Prints muſt be faſtned to a
Board entirely ſeparated from the Machine, which
Board muſt be ſet upon a Support, that may
conveniently be moved backwards or forwards,
according to Neceſſity.
fame as that of the Firſt; but it ought to be ob-
ſerved, that when we incline the Machine, 2243. Angle of Inclination of the Mirrour and Hori-
zon muſt be made leſs, by half the Inclination of
the Bottom of the Box; and when the Machine
is ſomewhat inclin’d backwards, the ſaid 3344. muſt be made greater by a like half. You muſt
likewiſe obſerve, that when Objects are to be
repreſented for a perpendicular Picture, the Ma-
chine muſt be placed according to the former
Part of Numb. 44. Prints muſt be faſtned to a
Board entirely ſeparated from the Machine, which
Board muſt be ſet upon a Support, that may
conveniently be moved backwards or forwards,
according to Neceſſity.
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