420 BOOKBINDING 



ing) is that mostly employed for securing tho folded shoots together. For this 

 purpose the sowing press is employed. 



Ifig. 157 represents the sowing press as it stands upon tho table before which the 

 workwoman sits. Fig. 168 is a ground plan without tho parts a and n in tho 

 former figure. A is the base board supported upon the cross bars m n marked with 

 dotted lines in fig, 158. 



Upon the screw rod rr, fy. 157, the nuts td serve to fix the flat upper bar n at 

 any desired distance from tho base. That bar has a slit along its middle through 

 which tho hooks below z z pass down for receiving the ends of the sewing cords or 

 tapes (from two or three to six in number according to the size of the volumes under 

 operation) pp fixed atyy and stretched by the thumbscrews zz. The bar yy is let 

 into an oblong space cut out of the front edge of the base board and fixed there by a 

 moveable pin a and a fixed pin at its other end round which it turns. The cords or 

 bands are fixed at distances and in numbers corresponding to the saw or pencil-marks 

 before named, made in the backs of the folded sheets, and tho cross cords be- 

 come embedded in the saw-marks by the pressure of the sewing thread. This is 

 drawn through the middle of each sheet and turned round each band beginning at 

 the first sheet and proceeding to the last. Tho first sheet being thus sewn and 

 secured to the bands, the second sheet is laid upon it, the thread carried from the 

 first sheet to the second, and the process is repeated, and so on to tho concluding 

 sheet of tho volume, the whole being connected together by the cross bands (whether 

 of cord or tape) round which the thread passes, first through one sheet, and then from 

 each sheet to its successor. 



A third method of securing the leaves of a book was some years ago introduced by 

 Mr. W. Hancock, namely, by tho adhesion of tho back edges of each leaf of the book 

 to a coating of caoutchouc and its superimposed lining cloth. In this method, instead 

 of the fold of each sheet or section (consisting of 4, 8, 12, 16, or 24 pages) forming a 

 back through which the needle of the sewer passes, as before described, the whole of 

 the back of the book is cut through by a plough knife or guillotine so as to present a 

 smooth level surface formed of the back edges of the book, which, if separated, would 

 then consist of single detached leaves. 



This smooth surface is slightly rasped so as to give greater facility for the adhesion to 

 the edge of each leaf of tho caoutchouc, a solution of which is applied in two or three 

 coats, at intervals sufficient to allow each coat to become firmly adhesive. Strips of cloth 

 lining are laid over this, and fastened on with caoutchouc, the outermost strip being 

 so much wider than the back of the book as to form a fly or projecting strip at each 

 side for the purpose of securing tho volume to the boards which form, with cloth or 

 leather, the cover of the book. We thus see that, instead of leaves attached by thread 

 at certain points or intervals, each single leaf is agglutinated continuously along the 

 whole length of its back edge to tho caoutchouc and cloth lining before described. 

 Books bound in this way open so perfectly flat upon a table without strain or resi- 

 lience, that they are equally comfortable to the student, the musician, and the merchant. 

 And where a book consists of paper at once thick, tough, and absorbent, tho adhesion 

 of each single leaf by its back edge to the caoutchouc coating and lining is generally 

 perfect, and, with careful usage, moderately durable. On tho other hand, when the 

 paper composing tho book is thin or non-absorbent, the adhesion of each loaf is very 

 uncertain ; and moreover, by frequent use, and especially under tho chemical effect of 

 atmospheric and climatic changes, tho caoutchouc sooner or later loses its adhesive 

 power over paper of any quality, hardens, cracks, and shrinks, and leaf after leaf 

 becomes more or less insecure and detached. The use of caoutchouc for book- 

 binding has therefore become far less general than was at one time anticipated, and 

 the needle and thread of tho workwoman is still tho general medium for connecting 

 the leaves of a book together. 



Hitherto we have dealt with the preliminary processes of securing tho separate portions 

 of a volume processes which arc common to all kinds of binding, from the simple 

 pamphlet with, or without its paper wrapper, to the most elaborately bound volume* 

 in russia or morocco ; except that in tho more expensive styles of binding, additional 

 care is taken in the process of sewing ; the thread being more frequently passed through 

 each section, round the cross bands, and from section to section, and more elaborately 

 secured. 



The next process is that of inserting tho volume into its cover ; and in this, two 

 systems are adopted : one, tho original plan of attaching tho boards of the cover by 

 drawing tho cross cords or bands through holes pierced through each board at its 

 back edge, then fastening tho leather or other material used for covering the book 

 over tho board, and subsequently adding tho lettering and ornament required ; tho 

 other that of the more modern ' case-binding.' This is now. from its comparative 



