GEOMETRICAL PERSPECTIVE. 



picture plane, 43'. .'/ / the eye, 7 feet ; nearett angle, 1 



foot 6 inc/u'5 to the right of the eye, and touching the picture 



Distance of the eye from the picture plane, 11 feet 6 



A iluorway to b constructed upon the uppermoit landing, 



it* proportions at pleasure. Scale, ^. 



Moat of the rules applicable to thiH problem, in the introduc- 

 tory Rtagea of its construction, hare been already given in 

 former leasons. We will merely refer to the details previously 

 explained in their order, and pass on to those which especially 

 - to the subject. The nearest angle touching the picture 

 plane is at a ; the ground line of the ends of the steps is 



and upon it draw the ends of the step* in contact with the face 

 of the balustrade, in the same way a* those were on the iodine 

 from a. 



We are now about to use the half distance point (see Tsescin 

 XIII.). From g commence* the retiring edge of the landing, 

 g n, which is a retiring line of 8 feet ; o U the half distance point. 

 Directed by this point, draw a line from h to , and make It 

 equal to 4 feet. Bole from k back again to m ; draw the per- 

 pendicular m n ; g n will then be the retiring edge of the land- 

 ing, directed to VP>. From n draw an inclined line to vp. 

 Through n, from DVP, draw a line to meet the line of contact in 





directed to VP' ; the fronts to VP*. The angle of inclination of the 

 ascent is constructed from DVP I , meeting the perpendicular from 

 VP 1 at vi- J (see Problem XXXI., Fig. 53). Upon this inclined 

 line construct the profiles of a few steps, for a purpose to be 

 explained presently. The simplest way will be to mark the 

 width of each step, 1 foot 2 inches, on the HL, commencing at 

 DVP 1 , viz., 1, 2, 3, etc. From these points draw perpendicular 

 lines to cut and pass beyond the inclined line. The remainder 

 of this portion of the problem will be understood from the 

 figure. Draw from a on the PP a line of contact, and take the 

 distances a, 6, c, d, from the inclined line, commencing at DVP 1 , 

 and transfer them to a, b, c, d on the line of contact, making 

 seven divisions, because there are to be seven steps. Draw 

 lines from the points thus marked on the line of contact to Dvp 8 , 

 and where they cut the inclined line from o to VP 1 will be pro- 

 duced the positions of the angles of the steps. The ends of their 

 horizontal surface or tread must be drawn towards vp 1 . The 

 fronts of the same must be drawn to VP*, and the rise will be 

 represented by perpendicular lines meeting the horizontal edges 

 of the steps. For the lengths, the distance of 8 feet must be 

 set off from a to e. A line drawn from e to DVP 2 will determine 

 af, the perspective width. From /a line must be drawn to VP, 



DVPJ 



p. Make p, q, r, s, and t equal to the distances a, b, c, d, etc., 

 below. Draw from q, r, t, t to DTP*, cutting the inclined line 

 from n to vp 3 , for the purpose of constructing the four remaining 

 steps above the landing. These most be done in the same way 

 as those between a and g. To draw the balustrade, produce a 

 line from / to meet the picture plane in the point of contact 4 : 

 4 s will be the line of contact. Draw a line through / from 

 DTP* to v ; make v w equal to 2 feet ; role back again to produce 

 x. The width of 2 feet is out off by drawing a line from J, 

 directed by DVP 2 , to e ; make e 5 equal to 2 feet ; role from 5 

 back again to 6. The horizontal parts of the balustrade most 

 be drawn towards VP', and the remaining portions up the incline 

 must be directed towards VP*. 



