The first line being thus finished, the compositor proceeds to the next; in order to do which he removes the brass rule from behind the former, and places it before it, and thus composes another line against it after the same manner as before; going on thus till his stick is full, when he empties all the lines contained in it into what is called a galley, which consists of a flat piece of mahogany, or other fine wood, with a ledge of a proper height at the margin of its two sides. The compositor then fills and empties his composing-stick as before, till a complete page is formed; when he ties it up with a cord, and, setting it by, he proceeds to the next, till the number of pages constituting a sheet is completed; which done, he carries them to the imposing-stone, there to be ranged in order, and fastened together in a frame called a chase, - and this is termed imposing. The chase is a rectangular iron frame, of different dimensions, according to the size of the paper to be printed, having two cross-pieces of the same metal, called a long and short cross, mortised at each end, so as to be taken out occasionally.

By the different situations of these crosses, the chase is fitted for different volumes; for quartos and octavos one traverses the middle lengthwise, the other broadwise, so as to intersect each other in the centre; for twelves and twenty-fours, the short cross is shifted nearer to one end of the chase; for folios, the long cross is removed entirely, and the short one remains in the middle; and for broadsides, no cross is required. To impose, or arrange and fix the pages in the chase, the compositor makes use of a set of furniture, consisting of slips of wood of different dimensions, somewhat lower than the letters; some of these are placed at the top of the pages, and called head-sticks; others between them, to form the inner margin; and others, in the form of wedges, to the sides and bottoms of the pages. Thus all the pages being placed at their proper distances, and secured from being injured by the chase and furniture placed about them, they are all untied, and fastened together by driving up small wedges of wood, called quoins, between the slanting side of the foot and the side-sticks and the chase, by means of a piece of hard wood and a mallet; and all being thus Bound fast together, so that none of the letters will fall out, it is ready to be committed to the pressmen.

In this condition, the work is called a form; and as two of these forms are in most cases required for every sheet, it is necessary the distances between the pages in each form should be placed with such exactness, that the impression of the pages in one form shall fall exactly on the back of the pages of the other; the effecting this is called making register.

As it is impossible but that there must be some mistake in the work, either through the oversight of the compositor, or by the casual transposition of letters in the cases, a sheet is printed off, which is called a proof, and given to the corrector, who, after reading it over, and rectifying it by the copy, making the alterations in the margin, returns it to the compositor to be corrected. The compositor then unlocking the form upon the correcting stone by loosening the quoins or wedges, rectifies the mistakes by picking out the wrong letters with a slender sharp-pointed steel bodkin, and putting others into their places. After this, another proof is made, and corrected as before; and lastly, there is another proof called a revise, which is taken from the form when finally placed on the press, in order to ascertain whether all the mistakes marked in the last proor have been corrected.

The pressman's business is to work off the forms thus prepared and corrected by the compositor; in doing which, there are four things required - paper, ink or colouring matter, balls or rollers, and a press.

To prepare the paper for use, it is to be first wetted by dipping several sheets together in water: these are afterwards laid in a heap over each other; and to make them take the water equally, they are pressed close down with a weight at the top.

The ink is made of oil and lamp-black; for the manner of preparing which, see Ink.

The balls, by which the ink was formerly applied on the forms, were a kind of wooden funnels with handles, the cavities of which were filled with wool or hair, as was also a piece of leather or pelt nailed over the cavity, and made extremely soft by soaking in urine, and being well rubbed. One of these the pressman took in each hand, and applying one of them to the ink-block, daubed, and worked them together, to distribute the ink equally, and then blacked the form, which was placed on the press, by beating with balls upon the face of the letter. A considerable improvement on this plan has been effected by means of rollers, which are now generally in use. These consist of a cylinder made of a combination of treacle and glue, which runs on an iron rod, affixed to which are two handles. Instead of beating, as in the former case, the cylinder is rolled over the face of the form, by which the ink is applied in a much more even manner, and with a considerable decrease of labour.

The earliest printing presses were the common large wooden screw presses, employed at the present day for compressing paper, cloth, etc. Of course this mode of taking impressions must have been very slow and laborious; and the pressure being applied between the two solid inelastic surfaces, a considerable degree of care must have been exercised to prevent injury to the letters or type of the form. Such presses were, however, used for about 300 years, without any one attempting to improve them. A short time previous to the year 1770 it appears that William Jansen Blaew, a mathematical instrument maker, of Amsterdam, recommended the introduction of a spring, both over the head and under the bed of the press, which, upon trial, proved very satisfactory; he took upon himself an alteration of the working screw, giving it more threads, which is, in effect, a quicker motion; and this, combined with the action of the springs, rendered the impression "sharper," without "hardness." Blaew's presses were found to be so great an improvement upon their precursors, that Luckcombe, in his History of Printing, published in 1770, says, "There are two sorts of presses in use, the old and the new fashioned; the old sort, till of late years, were the only presses used in England." Now the " new-fashioned " press of Blaew, though it has become very old-fashioned to modern printers, is too respectable a machine, in our eyes, to be wholly omitted in these pages; and as it differs not in any considerable degree from the wooden-framed presses still in use by many of our printers, we shall here annex a description which will sufficiently apply to them both.