382 PERSPECTIVE. 



described, by laying its width from D to R, and 

 drawing to the distance-point K. By raising the 

 perpendicular in the middle, you will meet the 

 ridge-line from the other gable in d. The other 

 method is as follows : Through the centre of the 

 picture G draw the line S T, upwards, and down- 

 wards, and perpendicular to the horizontal line. 

 Then continue the line of the roof B d till it meet 

 S T in S. From A draw A S, which will give the 

 other gable, and S will be the vanishing point for 

 all hues parallel to B rf and Ad; if N E be conti- 

 nued in like manner, it will give T for its vanish- 

 ing point. The doors and windows on the side 

 A B C D are laid down from a scale, because that 

 side, being parallel to the picture, does not vary 

 from its geometrical delineation, except shewing 

 the thickness of the reveals, or edges of the doors 

 and windows. If there had been any windows in 

 the side B E F C, they would be drawn in perspec- 

 tive by the same method that was used for finding 

 the width of the house and the middle of the end ; 

 viz. by laying off the actual dimensions from C upon 

 CI, and drawing from these points to the distance- 

 point K, which would transfer these divisions to 

 the bottom of the house CF, and then perpendicu- 

 lars might be drawn upwards. 



This practice is farther explained by the follow- 

 ing rule. 



To divide a line in perspective which is parallel 

 to the horizon, and which tends to a vanishing- 

 point, into any number of equal parts; or to divide 

 it in any required proportion. 



Let A B be the line going to its vanishing-point 

 C (Fig 2.); and first let it be required to divide 

 that line into six equal parts. Let C D be the hori- 

 zontal line, and AE the ground-line drawn parallel 



10 



