The text is a detailed guide on how to draw architectural perspectives of windows and galleries. It explains using perspective lines and geometrical calculations to ensure accurate proportions and positioning of elements in drawings. The instructions emphasize using certain points of reference and measuring distances to create realistic architectural renderings.
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You will notice that the square represented in perspective by KX lk is in the front, at the level of the wall surface. The other, represented by hiamn, is set back deeper and serves as a frame for the windows. It is in this latter square that you find the center of the window. From angle h to angle n, and from angle m to angle j, two diagonals are drawn that intersect at a point, through which the vertical represented here by qs passes, giving the center of the window and its opening or the junction line of the panels.
To draw the window panes, divide the side represented by KX into as many parts as there are panes to represent; upwards and from all these points of division, o, p, r, z, draw lines to the convergence point M, and at the same time the double lines forming the frames. By extending these lines, you find the corresponding divisions of the panes for the second window. The same method can be employed to find the recess of this second window. By extending the lines 8ne and fin, they will be intersected at points 8 and 9 by lines drawn from points 6 and 7 to the convergence point L, and the lines 8.6 and 9.7 would complete the depiction of the thickness or recession required.
It has been noted that throughout the previous demonstration the point of view has not been used to draw any lines. It may be required if in this room there is some furniture or object whose lines or edges form a right angle with the ground line, like the stool depicted here at the center of the room. The line AB’ being parallel to the ground line AC the vanishing lines of this figure will converge at the point of view at V.
Drawing a Gallery from Nature.
We assume the observer is far enough away to see, without turning the head, the entire width of the gallery, as represented here, plate 7, figure 3 (see also plate 6, figure 1 ). As for the height, it's almost impossible to see the entire height from the first plan. This gallery is assumed to be very tall, where one would need to move far back to see the entire height without lifting their head. We assume therefore that the view, for this first plan, embraces in height just a small distance above the first pillar on the right and the first column on the left.
Since these plates are only intended as guides in demonstrations, it was deemed necessary here to depict these pillars on one side and columns on the other, even though this combination is not according to architectural rules, but to train students in two types on the same plate. The paper is given a width that represents the width of the gallery in drawing, width represented here by AB. The first step is to compare, using the crayon holder, the distance from the first plan or line AB to the base of the first pillar, with width. Here the distance from EF to AB is equal to a sixteenth of AB. Therefore, starting from the ground line or first plan on the paper, a sixteenth of this ground line in width is marked by a point. A horizontal line, represented here by EF, is then drawn through this point parallel to the ground line.
To find the distance from the pillar to the line represented by BD, first take the line FG which represents the separation line of the two sides of the pillar. The crayon holder is held horizontally and the distance from FG to BD is compared with the total width of the board. This distance from FG to BD is found to be a small quarter of the total width of the board. Hence, on the line AB of the drawing and from B to A, a distance equal to the small quarter of AB is taken, and by the division point thus found, a vertical is drawn.
Then compare (still using the crayon holder) the total height of the pillar, represented by FG with width AB. Here, FG is approximately three-fourths of AB. Take therefore on the vertical of the drawing corresponding to FG, and from the point where this vertical cuts the line EF, a height of approximately three-fourths of the width AB of the drawing.
Compare the height of the capital with the total height FG. Here the height HG of the capital is one twelfth of the total height FG. Hence, from the vertical FG of the drawing, at
Translation Notes:
Crayon holder: This refers to a tool used to hold drawing instruments for accurate measurement and comparison.
Capital: The term refers to the topmost member of a column or pillar, often elaborately designed in classic architecture.