A text book of geometrical drawing, for the use of mechanics and schools, in which the definitions and rules of geometry are familiarly explained (1849)
front arch^ willbe the centres for drawing the other arches; R being the centrefor describing the front of the first rib. 7th. The joints in the fronts of the projecting ribs radiate to theirrespective centres^ and the joints in the soffit of the arch radiateto the point of. sight. Note.—No attempt… … W}I£j-Lifu. PLATE XLVIII. 99 Figure 2. To draw Semicircular or Pointed Arcades on either side of thespectator J running parallel to the middle visual ray. N. P andQ. O the width of the arches being given, and P. Q the space be-tween them, 1st. From JV*. P. Q and 0 erect perpendiculars^ make them…
