DOI Page / Citation link:
https://doi.org/10.11588/diglit.62828#0334
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the vifual d V in that fame proportion. The line J d being di-
vided into two equal parts, a line from 2, parallel to the hori-
zon, will cut at 4, which divides the vifual d N into two equal
parts; and a line from the point 4, perpendicular to the hori-
zon, will divide r V in the fame manner. Hence it is evident,
that if j d, 4, be divided into the fame number of equal parts5
a line drawn through any two correfpondent divifions, will tend
to V, the vanifhing point. It is alfo evident, by the fame mode of
reafoning, that if the half diftance j d were produced to twice its
prefent length, which would then be the whole diftance, a line
from d to V would be equal to the fpace from V to M, on the
left the true meafuring point, in the fame manner as d v mea-
fures w m, which is only half that fpace.
Of reducing tbe Point of Diflance, fo as to bring it within the
Limits of the Picture.
In making deiigns on a large fcale, it is very common for
the point of diftance to exceed the bounds of the paper or board
we draw on: to avoid the inconvenience of which, let the fol-
lowing problem be attended to.
Prob,
the vifual d V in that fame proportion. The line J d being di-
vided into two equal parts, a line from 2, parallel to the hori-
zon, will cut at 4, which divides the vifual d N into two equal
parts; and a line from the point 4, perpendicular to the hori-
zon, will divide r V in the fame manner. Hence it is evident,
that if j d, 4, be divided into the fame number of equal parts5
a line drawn through any two correfpondent divifions, will tend
to V, the vanifhing point. It is alfo evident, by the fame mode of
reafoning, that if the half diftance j d were produced to twice its
prefent length, which would then be the whole diftance, a line
from d to V would be equal to the fpace from V to M, on the
left the true meafuring point, in the fame manner as d v mea-
fures w m, which is only half that fpace.
Of reducing tbe Point of Diflance, fo as to bring it within the
Limits of the Picture.
In making deiigns on a large fcale, it is very common for
the point of diftance to exceed the bounds of the paper or board
we draw on: to avoid the inconvenience of which, let the fol-
lowing problem be attended to.
Prob,