This section is from the book "Spons' Mechanics' Own Book: A Manual For Handicraftsmen And Amateurs", by Edward Spon. Also available from Amazon: Spons' Mechanics' Own Book.
Ink used in drawing should always be the best that can be procured; without good ink a draughtsman is continually annoyed by an imperfect working of pens, and the washing of the lines if there is shading to be done. The quality of ink can only be determined by experiment; the perfume that it contains, or tin-foil wrappers and Chinese labels, are no indication of quality; not even the price, unless it be with some first-class house. It is better to waste a little time in preparing ink slowly than to be at a continual trouble with pens, which will occur if the ink is ground too rapidly or on a rough surface. To test ink, a few lines can be drawn on the margin of a sheet, noting the shade, how the ink flows from the pen, and whether the lines are sharp. After the lines have dried, cross them with a wet brush: if they wash readily, the ink is too soft; if they resist the water for a time and then wash tardily, the ink is good. It cannot be expected that inks soluble in water can permanently resist its action after drying; in fact, it is not desirable that drawing inks should do so, for in shading, outlines should be blended into the tints where the latter are deep, and this can only be effected by washing.
Pens will generally fill by capillary attraction; if not, they should be made wet by being dipped into water. They should not be put into the mouth to wet them, as there is danger of poison from some kinds of ink, and the habit is not a neat one. In using ruling pens, they should be held nearly vertical, leaning just enough to prevent them from catching on the paper. Beginners have a tendency to hold pen3 at a low angle, and drag them on their side, but this will not produce clean sharp lines, nor allow the lines to be made near enough to the edges of square blades or set squares. The pen should be held between the thumb and first and second fingers,-the knuckles being bent, so that it may be at right angles with the length of the hand. The ink should be rubbed up fresh every day upon a clean palette. Liquid ink and other similar preparations are generally failures. The ink should be moderately thick, so that the pen when slightly shaken will retain it 1/5 in. up the nibs. The pen is supplied by breathing between the nibs before immersion in the ink, or by means of a small camel-hair brush; the nibs will afterwards require to be wiped, to prevent the ink going upon the edge of the instrument to be drawn against.
The edge used to direct the pen should in no instance be less than 1/16 in. in thickness : 1/14 in. is perhaps the best. If the edge be very thin, it is almost impossible to prevent the ink escaping upon it, with the great risk of its getting on to the drawing. Before putting the pen away, it should be carefully wiped between the nibs by drawing a piece of folded paper through them until they are dry and clean.
With all forms of dotting pen a little knack is required in using. If straight lines are to be produced, it is advisable to lay a piece of writing paper right up to the place where the line is intended to commence. By this means it is readily discovered if the pen is working well. It also avoids a starting-point on the drawing, which very com-mouly leaves a few dots running into each other. For drawing circles with the dotting pen, fixed in the compass, the same precaution is necessary. The paper may bo pushed aside as soon as it comes in the way of completing the circle. Another necessary precaution 'with dotting pens is not to stop during the production of a line. In all dotting pens the rowels have to be made rather loose to run freely, and by this cause are liable to wobble; to avoid this, the pen should be held slightly oblique to the direction of the line, so as to run the rowel against one nib only.