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These two angles along the vertical that is raised at point e determine the width of the lateral perspective plan of the house. Connect points b and e with a line, and points d and f with another line to complete the lateral perspective plan befd, representing the model house plan befd.

To find the roof, compare the height of the roof to the height of the house. Here, the height GL of the roof equals a quarter of the height AC of the house (fig. 8). Thus, take the height equal to a quarter of AC, the height of the house (fig. 7). This height would then be transferred above the line ed, and thus the height of point z is determined, through which a line parallel to cd will pass. However, the roof's top is narrower than its base. By holding the pencil vertically so that it hides the angle represented by G, you will find that G is vertically above point L, which is distant from angle C by the distance CL that is equal to a third of CD. From point c, take a third of cd and find point z through which a vertical will be drawn to complete the positioning of point g. Connect points e and g. Determine the line of angle i using the same method, and draw lines hd and hf to complete the sketch of the model house, or figure 8, as represented in figure 7.

If you compare the result you have obtained (figure 7) with the process from plate 3, figure 10, you will see that it was the same. The only difference to note here is that the house being drawn is taller than the draftsman, causing the viewpoint to be below the roof, even when it is positioned just like that in figure 10, plate 3. If you extend the lines d, f, g (fig. 7), they converge at a point that is the vanishing point of all these house lines. This vanishing point is here at v (fig. 7) and in v (fig. 8), near the house, at the end of the avenue.

Proceed by placing the windows in the geometrical plan, comparing the height of the windows with the height of this geometrical plan represented by ABCD, or with the roof's height. The distance between the top of each window and the base of the window in the story above can be calculated in the same way by relating it to the previously found window heights. Similarly, the width of the windows is found by comparing it with their height. This process should be done by eye and using the pencil lever, as demonstrated in plate 2, figure 3.

The height of the door is found just like the height of the windows. The chimney heights should also be determined in practically the same way, each with a geometrical plan and a perspective plan directed towards vanishing point V (fig. 8). Compare the chimney's height again to the panorama and the height of the roof or the house.

For windows in the perspective plan, find the first one, which will determine all others, assuming that the house being drawn has similar windows. This first window is found using the ordinary comparison method. If the windows in the model's perspective plan (fig. 8) are similar to those in the geometrical plan, it's repeated on e equal to height mp on side DB. From points r and s, draw two lines to vanishing point V. This provides the diminution in window height in the perspective plan. The second window will seem less tall, and the third less tall than the second. Widths must also decrease, in the same proportion. Therefore, compare the width of the first recessing window to its height. Here, find that this width is a quarter of its height; so provide this first window with a width of a quarter of its height, the same principle applies to the others. The central width reductions will be found similarly.

If the space between the sides of the windows, or "entre-deux," is equal to the windows' width, a very simple method can be employed to find the reduction of these windows and these segments.

The first "entre-deux" ABCD (fig. 9) is found by comparing line AV, BV going to vanishing point V; these lines provide the height of the windows. Divide the first line AB.