Double Elephant ..
For making detail drawings an inferior paper is used, termed "cartridge"; this answers for line drawings, but it will not take colours or tints perfectly, Continuous cartridge paper is also much used for. full-sized mechanical details, and some other purposes. It is made uniformly 53 inches wide, and may be had of any length by the yard, up to 300 yards.
For plans of considerable size, mounted paper is used, or occasionally the drawings arc afterwards mounted on canvas or linen.
The linen or calico is first stretched by tacking it tightly on a frame or board. It is then thoroughly coated with strong size, and left until nearly dry. The sheet of paper to be mounted requires to be well covered with paste; this will be best if done twice, leaving the first coat about ten minutes to soak into the paper. After applying the second coat place the paper on the linen, and dab it all over with a clean cloth. Cut off when thoroughly dry. (See also v. 28.)
The stretched irregular edges of the sheet of paper are cut off against a flat ruler, squaring it at the same time. The sheet of paper is laid upon the board the reverse side upwards to that upon which the drawing is to be made. It is then damped over, first by passing a moist clean sponge, or wide brush, round the edges of the paper about an inch and a half on, and afterwards thoroughly damping the whole surface except the edges. Other plans of damping answer equally well; it is only necessary to observe that the edges of the paper should not be quite so damp as the other part of the surface. After the paper is thoroughly damped, it is left until the wet gloss entirely disappears; it is then turned over and put in its position on the board. About half an inch of the edge of the paper is then turned up against a flat ruler, and a glue-brush with hot glue is passed between the turned-up edge and the board; the ruler is then drawn over the glued edge and pressed along. If upon removing the ruler the paper is found not to be thoroughly close, a piper-knife or similar article passed over it will secure perfect contact. The next adjoining edge must be treated in like manner, and so on each consecutive edge, until all be secured.
The contraction of the paper in drying should leave the surface quite flat and solid.
If the point is intended for sketching, it is cut equally from all sides, to produce a perfectly acute cone. If this be used for line drawing, the tip will be easily broken, or otherwise it soon wears thick; thus, it is much better for line drawing to have a thin flat point. The general manner of proceeding is, first, to cut the pencil, from two sides only, with a long slope, so as to produce a kind of chisel-end, and afterwards to cut the other sides away only sufficient to be able to round the first edge a little. A . point cut in the manner described may be kept in good order for some time by pointing the lead upon a small piece of fine sandstone or fine glass-paper; this will be less trouble than the continual application of the knife, which is always liable to break the extreme edge.
To erase English lead-pencil marks, native or bottle rubber answers perfectly. This, however, will not entirely erase any kind of German or other manufactured pencil marks. What is found best for this purpose is fine vulcanised rubber; this, besides being a more powerful eraser, has also the quality of keeping clean, as it frets away with the friction of rubbing, and presents a continually renewed surface to the drawing; the worn-off particles produce a kind of dust, easily swept away. Vulcanised rubber is also extremely useful for cleaning off drawings, as it will remove . any ordinary stain.
For erasing ink lines, the point of a penknife or erasing knife is commonly used. A much better means is to employ a piece of fine glass-paper, folded several times, until it presents a round edge; this leaves the surface of the paper in much better order to draw upon than when erasures are made by a knife. Fine size applied with a brush will be found convenient to prevent colour running.
To produce finished drawings, it is necessary that no portion should be erased, otherwise the colour - applied will be unequal in tone; thus, when highly-finished mechanical drawings are required, it is usual to draw an original and to copy it, as mistakes are almost certain to occur in delineating any new machine. Where sufficient time cannot be given to draw and copy, a very good way is to take the surface off the paper with fine glass-paper before commencing the drawing; if this be done, the colour will flow equally over any erasure it may be necessary to make afterwards.
Where ink lines are a little over the intended mark, and it is difficult to erase them without disfiguring other portions of the drawing, a little Chinese white or flake-white, mixed rather dry, may be applied with a fine sable brush; this will render a small defect much less perceptible than by erasure.
Whenever the surface of the paper is roughened by using the erasing knife, it should be rubbed down with some hard and perfectly clean rounded instrument.
Persons with limited means will find it better to procure good instruments separately of a respectable maker, Stanley or Harling for instance, as they may be able to afford them, than to purchase a complete set of inferior instruments in a case. With an idea of economy, some will purchase second-hand instruments, which generally leads to disappointment, from the fact that inferior instruments are manufactured upon a large scale purposely to be sold as second-hand to purchasers, principally from the country, who are frequently both unacquainted with the workmanship of the instruments and with the system practised.