THE ART OF DRAWING. | 149 
before the same in such a manner that it is in contact with one corner or 
edge of the body, forming with its principal front an angle of less than 45°. 
If a number of objects are to be drawn in one group, the rule is to place 
the transparent plane parallel to the front of one of them (pl. 19, jigs. 
40-45). In drawing inclosed spaces (rooms, churches, &c.), the front wall 
is ugually imagined as removed and replaced by the transparent plane and 
the eye of the draughtsman on its exterior side. In drawing an open 
landscape, and this is the most difficult case, two points on the ground 
have to be selected and retained, through which the transparent plane is 
imagined to pass vertically; whilst the plane itself must be imagined as 
bounded on the right and left sides by perpendiculars, and above and 
below by horizontal lines, these four lines encompassing everything in the 
landscape that is to be included in the picture, and excluding everything 
that is not to be drawn. The boundary lines of the fictitious transparent 
plane must then correspond with the lines circumscribing the paper or the 
plane of the picture. 
The dzstance of the draughtsman from the transparent plane must at least 
be great enough to allow the eye to survey its limits without any motion of 
the head, either sideways, or upwards, or downwards. A common distance 
is the diagonal or better twice the length of the transparent plane. If the 
distance be chosen too small (pl. 19, jig. 48) the eye is easily fatigued in 
the survey, and the objects appear as unusual images, wm perspective distor- 
tion. Lig. 44 offers a favorable contrast, being taken from the right dis- 
tance, whilst jig. 43 is taken from a distance not exceeding the breadth of 
the image. On the other hand, if the distance be chosen too great, the 
smaller parts of the object lose in clearness, and the picture fails in express- 
ing the depth to which the receding parts extend. 
The altitude of the pownt of view before the transparent plane above the 
base of the latter, 7. e. the height of the point of sight or of the horizon in 
the drawing, is most natural at the elevation of the eye of a standing man 
above the ground (pl. 19, jigs. 42, 45). If the ground be covered by but 
few objects, or if it be empty or barren, the altitude of the point of view 
should be decreased ; the ground will then appear less extended in the pic- 
ture. If the altitude be too limited the appearance of the ground will 
approach too much that of a straight line, and the objects on it will cover 
each other too much. If on the other hand it be too great (fig. 42) the 
ground will appear too extended, the lines on it too steep, and the objects 
in the depth too much as if they were placed above each other; and if the 
point of view be higher than the upper surfaces of the objects, the draw- 
ing will have the appearance of a horizontal projection: in landscapes that 
of a topographical map. ‘The proper height of the point of view can only 
be determined for every special case by a practised judgment, developed by 
continued drawing from nature. 
The lateral position of the point of view with respect to the vertical axis of 
the transparent plane varies according to the object to be drawn. If this be 
a single rounded object the draughtsman places himself precisely opposite the 
axis of the plane, or so that the line of sight intersect it at right angles (pl. 
533 
