The text explains how to use visual comparisons to draw various elements within a room, focusing on paintings, the fireplace, and the carpet using principles of perspective. It details how to measure and compare dimensions for these components to keep consistency and perspective. Techniques include checking alignments with vertical and horizontal lines and drawing ellipses and circles in perspective.
The height and attachment of all three are at the same distance from the ceiling. To find the widths of the same paintings, one compares by eye and on the paper holder the width of each painting with its height.
As these paintings are also assumed to be equally inclined, the side ZY of the second is parallel to TX of the first, and so on. All the vanishing lines of these paintings should converge to the point of view. The painting placed above the sofa is supposed to be straight applied against the wall. The two sides that are vertical should be drawn vertically: the other two sides converge to the point of view.
Now it's a matter of drawing the back of the room.
The two paintings located on this side of the room, represented here by abcd, are found like those mentioned earlier. One compares the height of these paintings with the wall: one finds their inclination, assuming a vertical that could be indicated by the paper holder, starting either from the angle represented here by k, or from the angle represented by l. Then compare the width of these paintings with their height.
The width of the fireplace is compared with the width of the wall ab. The width of the fireplace is here the larger third of that of the back wall. On the drawing, find the large third of the line represented here by ab, and in the middle of which one takes this large third, which will represent the width of the fireplace. Compare the height of the fireplace with the width. This height is here the double of the width. On the drawing, take the double of the width found to see the height. Finally, this fireplace is drawn like the box, taken to model board 3, figures 6 and 7.
The two vanishing lines, those above converging to the point of view. As for the vanishing lines of the interior, they converge at accidental points. By holding the paper holder horizontally, one sees at what height the end of one of these lines cuts one of the verticals at the sides of this fireplace. The same method is applied for the other vanishing lines of the interior.
The width of the frame and the small square at the back should be compared again with the width of the fireplace. As the fireplace projects into the room, one will see again, by holding the paper holder horizontally, how much the bottom of this fireplace appears to descend below the line represented here by ab. The height of the mirror is compared with that of the wall. The height of the armchairs is compared with that of the fireplace.
The vanishing lines of the carpet converge at the point of view; the middle rosette is composed of several circles in perspective or ellipses. The largest diameter is compared to the width of the floor, and then the smaller diameter to the large one. (See board 4, figure 11bis.)
The patères near the windows are also circles seen in perspective or ellipses. After having compared the largest diameter of one of the ellipses with the height of one of the windowpanes of the first window, and then the smaller diameter with the large one, the ellipse is finished. Then, having the large diameter of these ellipses, lines are drawn to the point of view, and between these two lines, the height of the other patères, which should appear to decrease in proportion to their distance.
We will not dwell on how to draw the lines forming the square border of the carpet from nature; they fit into the already demonstrated applications.
The lines of tiles traced here and before on the carpet would present more difficulty. We will refer to our treatise on Simplified Perspective for this subject, where we have given the way to put all sorts of floors and tiles in perspective, always keeping within the reach of beginners.
In the mirror placed on the fireplace, one sees the image of the side of the room that is opposite behind the observer. To find this repetition of the image in this mirror, one compares with the height of the mirror the distance that exists between the upper end of this mirror and the line marked here rz, which in the repeated image represents the line separating the ceiling from the wall on the side in front of which the observer is placed. One compares again the distance between this line and the top of the door, as one sees it repeated in the mirror. In the same way, one sees what the width of this door is. \/p>