The Line of the Plan is CD, the Perpendicular CI; the Geometrical Elevation of the Length of the Column, suppos’d to be lying on the Ground, is A. The Geometrical Plan thereof is B, with the Divisions of its Breadth on the Line ER. The Points of Length being transferr’d on the Line of the Plan CG, and the Points of Height EC into CF; from the Divisions of CG Lines are drawn to the Point of Distance; and from those of CF to the Point of Sight. From the Sections of the Visual CO, Perpendiculars are erected, and the Elevation H completed, from whence is taken the finish’d Column L.
If upon the Plan M you would delineate another Column, the Breadths thereof must be taken from the Column B, and another Profile design’d in N, which serves as an Elevation for making the Column P. If another Column were requir’d in the Angle, the Profiles HN assist you in the ready Performance thereof.
Fig. lxxxvii.
FIGURA Octogesimaseptima.
Præparatio necessaria ad sequentem figuram, & ad projectiones horizontales in laquearibus vel testudinibus.
Exhibet hæc figura in AA unum ex quatuor parietibus aulæ, cujus altitudinem veram IH velis attollere apparenter usque in L, pingendo in laqueari, vel in testudine, seriem balaustiorum. In B est vestigium geometricum quartæ partis laquearis. In C habetur elevatio medietatis latitudinis. In D est sectio coronicis & mutulorum. In E posita est elevatio medietatis longitudinis. In F est punctum oculi, in G punctum distantiæ: adeóque tota distantia est GF.