Numbers, letters or marks should not be placed on the face of photographic prints or wash drawings. If numbers or letters are called for, they should be indicated in pencil at the proper point on the back of unmounted prints. This can be done easily by holding the print against a window facing a strong light. In the case of mounted photographs, a fly leaf of thin paper pasted on the back of the photograph at the top and folded over the face of the photograph, can be used for the numbers or letters. In both cases the engraver adds the numbers or letters on the print in the manner best suited to reproduction.
Drawing for two-thirds reduction.
Two-thirds reduction.
Manufacturers' cuts can sometimes be used when the nature of the text calls for them. If possible the manufacturer should be asked to supply the original photograph or drawing. If this is not available, then the original cut—not an electrotype—should be secured. Electrotypes can often be used, but the results are not of the standard which we like to maintain.
Wax Cuts.—Formerly many textbooks were illustrated by engravings made by the wax process. This is the process ordinarily used for the production of maps. The cost of these engravings has risen, however, to a point which makes them now practically out of the question for the average book. They may be used in special cases. Their chief advantage is that they can be made from rough pen or pencil sketches and do not call either for finished lines or careful lettering.
In General.—Wherever possible illustrations to occupy a full page should stand vertically on the page. This is, we think, obviously more satisfactory to the user of the book.
Folded plates and charts should be avoided as far as possible, not only because they involve an unreasonable expense, but because American readers, at least, do not like them. Furthermore any considerable number of inserted charts weakens the binding of the book.