Another interesting development is in the relation of printing to the other lines of constructive work. It has proved extremely valuable to have the completed problems written up in descriptive articles by the pupils, and to have the best of these compositions printed.
THE ART OF PRINTING
Methods and Tools of Composition.
In printing, composition includes all the steps from receiving the copy until the type is set up, proofed, corrected, and made up into page forms.
This discussion presupposes a knowledge of spelling, syllabication, punctuation, paragraphing, etc., all of which good composition really includes. Practical rules bearing on these different phases may be found in various handbooks for the printer.
The first essential in printing is, of course, a quantity of type properly arranged.
Type is cast from a composition of metals—lead, tin, antimony, and sometimes copper. This composition is melted and poured into moulds the size and shape of the desired type.
Accuracy in Size of Type. Lead is used as the chief constituent of the composition, because it shrinks very little in cooling. This makes greater accuracy possible. Accuracy is an absolute essential in type, for thousands of pieces of metal must be held together in one form by a slight pressure at the sides and ends of the form.
Lead alone is too soft to wear well and to retain the shape of the type under the constant pressure of the printing press. Tin is added to give hardness, and antimony or copper to give toughness to the type metal.
Type Described. Type are small columns of the metal with a letter or character in relief on one end of each column, as at Fig. 1. The surface of this relief portion from which the letter or character is printed is called the face.