Page:An introduction to linear drawing.djvu/64
Thus, to raise an order of a given height, divide the height, as expressed in feet or inches, by the number of modules belonging to the order, and the quotient will be the module or semidiameter of the base of the col- umn. We say the base, because it is found that the column is more graceful if it insensibly diminishes to- wards the top, so as to lose one third of a module in the two upper thirds of the column.
The module, being thus ascertained, is divided into smaller parts, and thus gives the height of all the sub- divisions.
A vertical or perpendicular is drawn, on which are successively marked the lengths of the cornice, the frieze, the architrave, &c. On these points, horizon- tals are drawn, between which will be contained all the mouldings of the order.
Or—if the circumference of the base of a column be measured with a string, and multiplied by 0,159, the module will be found ; and from this, the height of the whole edifice, and of all its parts.
Pediments are triangular structures, whose height may be much varied according to their extent. There are some whose height is a third, fourth, fifth or sixth of the base. This proportion is left to the taste of the artist; and it is pretty much so with the various mould- ings which compose the cornices, capitals, &c.
Pilasters are square columns (parallelopipeds) sel- dom detached, but fastened to the wall or wainscot, and projecting nearly a third or fourth of a module. In other respects, their ornaments, capitals, base, and all their proportions are regulated by the rules of the order they belong to.