Stereotyping is the simple process of casting a printing plate in type metal from an impression of type made into plaster of paris or waxed papier-machΘ It was first developed in the eighteenth century, but was resisted as a form of automation that would put compositors out of work, as in fact it did when it began to be widely used on the cylinder press and even more on the rotary press, in which the impression was made onto the paper by an inked and type-covered drum. For the rotary press a curved stereo plate, easily made on a special caster, was more practicable than the alternative of imposing pages of type in "turtles" (special formes) around the cylinder. One of the workmen in the illustration is stocking the melting furnace. On the left is the casting-box or pot cooling in water. At the far right of the furnace is the casting area, where the casting boxes, containing moulds made from oiled formes of type, are completely immersed in hot metal to force all the air out. After ten minutes the box was taken out and a second workman used a mallet to release a usable forme, ready after some trimming and dressing had been done for printing.
The main advantages of stereotyping were: (1) if the work was to be printed again, the composition of a text by hand composition had to be done only once, since storage of stereotype plates was a simple matter; (2) the printer did not have to tie up large sums of capital in hand-cast type, but could get by with a smaller stock; and (3) extra stereotype moulds could be made for sale to publishers in other countries, so that the same book could be printed from the same setting of type in several different centres. Many of the books printed in Canada in Victorian times were probably printed from stereotype plates of British typesettings.
