The compasses, Fig. 24, are used to draw circles and circle arcs. They should be held at the top between the thumb and fore finger and spun around between them as the circle is drawn. If held by the legs there is a tendency to pull them together or force them apart thus spoiling the circle. Care must be exercised so that the needle point may not be pressed deeply into the paper as this will result in inaccurate work. Keep the needle and lead of even length by adjusting them when necessary.
This, Fig. 17, is used for ruling lines in ink and is held as shown in Fig 14. It is filled with ink by placing the quill of the drawing ink bottle between the nibs of the pen, when the ink will run between the nibs. The width of a line is determined by the adjusting screw on the pen. The pen should not be filled too full, as the ink is likely to drop out or run out quickly when passing across another inked line. Try the pen on the border of the plate before using it on the drawing. The compass pen is operated similarly. Always keep the nibs clean outside and never allow ink to dry between them, as this would rust the pen and clog it up.
For general erasing, a Faber Ruby eraser is very satisfactory as it may be used for both pencil and ink lines on paper or tracing cloth. The draftsman should have also a piece of Art Gum for cleaning off light lines or soiled places.
Use small thumb tacks, Fig. 13, for fastening the paper to the board; the large ones are more expensive and less satisfactory to use. Always press the tacks firmly down, as it is the head, rather than the pin, which holds the paper in place.
The architect finds use for several kinds of paper in his work.
Detail paper is a heavy paper used for the drawing of building details. It may be had in sheets or in rolls. The rolls vary in width from 36 to 54 inches and usually contain from 10 to 50 yards. A 36-inch roll may be cut,without waste, into sheets 36 by 26, 26 by 18, 18 by 13, 13 by 9, or 9 by 6 1/2 inches.
Tracing paper is a thin, white, transparent paper for general use where one drawing is to be made over another. It is much cheaper than detail paper and is ideal for sketches and scale drawings. It comes in rolls 30 to 50 inches in width and in various lengths.
Water-color paper is used where water-color renderings are desired. There are several kinds of good water-color papers, the two in most common use being the Italian "Fabriano" and the English "Whatman" paper. These are finished in three qualities, hot pressed (smooth surface), cold pressed (medium surface), and rough. The hot pressed is best for fine line work, the cold pressed for average rendering, and the rough for water-color sketches or bold work. The sheet sizes vary from 13 by 17 to 35 1/2 by 56 inches. The Imperial or 22 by 30-inch size is probably best for student work.
Bristol board is a cardboard for use in pen, pencil, or water-color rendering. There are two surfaces, the smooth for pen and ink, and the medium for pencil and for water-color. The board is made in a number of sizes and weights.
Drawing ink is a heavy "India Ink" especially prepared for this work. It comes in bottles with a quill in the cork for use in filling the pens.
See the article on lettering.