Page:An introduction to linear drawing.djvu/79

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ishing line. Tbe dotted lines in the cut will illustrate this better than any description.

fig. 4. plate ii.

Suppose it be required to find the perspective dis- tance of nine trees equidistant from each other. Draw the Base Line just the real length of the row of trees, or longer, at pleasure. Then draw the Horizontal Line longer than the base line. From the left end of the base line draw a Vanishing Line to any point on the horizontal line. Thep taking the length of this van- ishing line, take a portion of the Horizontal Line to the left of the Vanishing Point, equal to the vanishing line in length. On the Base Line measure the exact length of the row of trees, and divide the Base Line into exact portions according to the number of trees, and place a dot at each distance. Then draw a line from each of these dots to the point on the left of the Horizontal Line, and the points where these lines intersect or cross the Vanishing Line are the perspective positions of the trees. If you wish to regulate the height of the trees, draw another vanishing line from the top of the tree on the BaseLine to the vanishing point, and the distance be- tween the two vanishing lines will be the height of the trees, as is shown by the dotted line in the figure.

fig. 5. plate ii.

Figure 5 represents the perspective of a square, one of whose sides is parallel to the base line. First draw the base and horizontal lines, then from the two angles of the square which touch the base line carry the two vanishing lines to thé vanishing point on the horizontal line. From the same angles draw two lines, one to the right and the other to the left of the vanishing point, and at equal distances on each side of it. Then draw a line