2 8 The Ordoname os the Part I.

Ch. VIII. this Swelling, and to trace the Line of its Profile, so that the twoLines which make the Profile of the Column, bend towards theExtremities in the fame Proportion, bowing twice as much towardsthe Top as towards the Bottom, by reason the upper Part is twiceas long as the lower. Monf. Blondel , in his Tract: of the four prin-cipal Problems of Architecture, has shewn how this Line may bedescribed at one single Stroke, with the Instrument Nicomedes inven-ted to draw the Line calfd the first Conchoid of the Ancients. ThisMethod can serve only for the Line of Diminution, which goesfrom the Bottom of the Column to the Top, so that it does notbend inwards towards the Bottom, but falls perpendicularly : un-less one would have this Bending begin above the Third from theBottom, which ought to be strait, making two parallel Lines: Forin my Opinion, the Column ought not to be diminished below,since neither the Architects of the Antique^ nor even the greatestpart of the Modems have done it.