Elements of Science and Art, a Familiar Introduction to Natural Philosophy and Chemistry - Softcover

Reseña del editor

This historic book may have numerous typos, missing text or index. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. 1803. Not illustrated. Excerpt: ... Ord Names. New Names. Sulphate of copper 'i--of iron Vitriol, blue or Roman ', green ', martial, white Vitriols Water, acidulated hepatic drawing. Drawing is a very important art, and of the most extensive utility. To treat of it fully, and in the manner it deserves, is by no means an easy task, and would far exceed the limits of this work. As, however, some hints respecting it, will be found useful to those who have no opportunity of receiving regular instructions, we shall endeavour to comprize into as small a compass as possible, such directions and rules as are most generally useful. Geometry and perspective forming the surest basis upon which the art of drawing can be built, we shall begin by giving a few instructions in these sciences, after first describing the necessary implements. Of the Implements and Materials used in Drawing. Drawing-boards are for fixing the paper upon, so that it may not shift, and also for straining it, to prevent the. colours, when laid wet upon the paper, from causing it to swell up, so as to be uneven. The simplest sort is made of a deal-board framed square, with a strong piece across each end, to prevent warping. Upon this the paper may be fixed down with pins, wafers, or sealing-wax, or it may be strained with paste or or glue, as follows: having wetted the paper well with a sponge, lay it upon the hoard, and turning up the edges about half an inch, run a little good paste or glue all round on the under side, and press the paper down upon the board with a cloth; then set it by to dry: the paper, which had expanded and blistered up much when wet, will contract in drying, while the edges, being fixed immoveably, will strain quite flat and tight, and will be much better for drawing upon than when loose. The best kind of drawing-...