Fig. 115—Boards cut out at head.
First of all, the headband. It is carried on to each board 3 cm. deep, and the boards must therefore be cut out the same distance up to the edge; at A the board is bevelled off on the inside. Now cut a piece of coloured chamois leather—dark red or green—5 cm. wide and as long as the distance from one notch across the back to the other. The back at B is now glued, the strip of leather laid on so that it projects 1-1/2 cm. beyond the edge, and the ends at each side brought equally to the bevelled part A. At both sides these are pushed in under the thin board and well pasted down, whilst the piece projecting over the edge is glued and turned backwards; but in order to strengthen the piece on the back of the book, a piece of card as long as the width of the back is laid in.
The back is selected either from ready-made undressed leather backs of suitable length and width, or is made on the machine. The practice of pasting the backs at the edges only does not seem satisfactory, because on the one hand it does not give sufficient spring, and on the other the single sections easily work loose. For pasted backs, stout wrappers are taken, and the strips are cut so that each one slightly overlaps in width the one preceding. The glued and fitted strips are either pressed hot in the rounding press or put through a rolling machine built for the same purpose. The finished backs should be allowed to dry for a short time. Where there is no machine suitable for this work, the backs must be pasted into each other, beginning at the outside, and well rubbed down upon a board made with grooves of various dimensions. The older method of pasting the backing upon the book itself is still followed, although it does not produce the firm arch nor give such a good shape as the former method. When it must be done, the following is the way to proceed: The size is taken by laying a piece of paper across the back (taking in 1/2 cm. of the board on each side), and with the dividers this measure is marked out on a strip of wrapping paper, which must be the exact length of the board, but wide enough to project about a hand's width over each board. So that this should not have an unsightly appearance in the book, it is bevelled along each side.
Fig. 116—Suggestion for account book back. K—Pared edge; T—Part to be pasted.
According to the measurement marked by the dividers at top and bottom, a rule is laid from a to a, and along this a sharp line is drawn with the folder, and the lappets projecting underneath the rule are bent upwards. At this line thus marked, the wrapper is folded over and creased with the folder. A second parallel line is made in the same way, about 6 to 7 mm. farther out, from b to b. The back thus prepared is rounded in the middle part; a strip the size a to a might still be pasted in the centre. To fasten this to the book, both strips are glued with strong glue from b to the edge, the back brought into position, glued, and pressed down. From this it will be seen that the back stretched across the book is not glued on from a to b. A few more pieces of wrapping paper are still glued on to this first back to increase the strength of the arch; each one is measured separately after the one preceding it has been glued into its place, always measuring from a to a.
Fig. 117—Suggestion for account book back.
Such backs do not adhere quite firmly, and it is advisable to insert another narrower glued strip, opening the book in the middle, of course, to do this. After inserting the back, the book is closed, and the back will now lie close and tight to the book. It is trimmed at top and bottom with a sharp knife and finished off with a rasp if necessary.
The heavy boards are hinged on to this back. They are cut to fit, and, beginning at the fold b, are placed so that the edge of the board stands a little away from the joint.