This process has an advantage over every other hitherto employed in which machinery has been engaged; and it is, in some respects, preferable to beating, as the book is of the same thickness in every part, while in beating there is a great liability to beat the edges thinner than the centre; and the air appears to be as completely forced out as if the beating-hammer had been used; and there seems to be no disposition in the book to swell up again after undergoing this crushing process.
In some binderies a hydraulic press is relied upon for compressing the sheets, without their undergoing the beating or rolling process. For publishers' work it has been found to answer the purpose for which it is employed, as the press can be filled up by placing the books in layers of from one to four or eight, according to their size, between iron plates; and the immense power of the press is thus evenly distributed through a large quantity of sheets at the same time.
HYDRAULIC PRESS, FROM THE MANUFACTORY OF
ISAAC ADAMS & CO., BOSTON.
The power of compression is derived from the pump to the left of the press, which is supplied with water from a cistern sunk under it. The water thus sent, by means of the tube seen passing from it to the centre of the foot of the press, causes the cylinder to which the bed is fixed to rise and compress the books or paper tightly between the bed and head of the press. When it is forced as high as can be by means of the pump-handle seen, a larger bar is attached and worked by two men. The extraordinary power of this press is so great as to cause, particularly in common work, a saving of more than three-fourths of the time required in bringing books to a proper solidity by the common press. When it is wished to withdraw the books, the small cock at the end of the tube at the foot of the press is turned, the water flows into the cistern below, and the bed with the books glides gently down in front of the workman. Two presses are frequently worked by the same pump, one being on each side.
The hydraulic press is manufactured by nearly all the press-makers, differing only in the general design, the application of power being the same.
After beating, should there be any plates to the work, they, as before stated, must now be placed among the text. Great care must be taken to make the justification of the plates uniform with the text, by cutting off any superfluity at the head or back, and by placing them exactly facing the pages to which they refer, pasting the edge next to the back. Any that may be short at the head must be brought down, to preserve a uniformity. It is advisable to place a leaf of tissue-paper before each plate, particularly when newly printed, as the ink of copper-plates is longer in drying than that of letter-press. When a work contains a great number of plates, which are directed to be placed at the end, they are sewn on the bands by overcasting, which operation will shortly be treated of in full.
The book, being now ready for pressing, is taken in sections, according to the work and the judgment of the workman, and placed between pressing-boards the size of the volume, one on the other, and conveyed to the standing-press, which is pulled down as tight as possible by the press-pin, or fly-wheel, according to the nature of the standing-press; although it must be premised that when a book has been through the smasher, no further pressing will be required until it reaches the hands of the forwarder.
After the book has been sufficiently pressed, it will be necessary again to collate it, to correct any disarrangement that may have taken place during the beating and pressing. It is then ready for being sawn out.