SCIENCE IN THE INDUSTRIAL WORLD 



terial silks and fine leather, and gold, and "pearl" 

 trimmings but the covers with clusters of precious 

 gems, with gold hinges, clasps, and locks, and delicately 

 carved ivory, have passed away with the other relics 

 of the Dark Age. And yet the cover of the modern book, 

 as hi the case of the medieval tome, is usually the most 

 costly part of the volume. The relative values have 

 probably changed very little, for the manuscript volume 

 was expensive. 



In medieval times, and indeed until well into the eight- 

 eenth century, wood was the favorite material for the 

 sides of book-covers. Some of these covers of the early 

 period, with "their metal hinges, bosses, guards, and 

 clasps, seem, in all but dimensions, fit for church doors." 

 But as soon as the printing-press came upon the scene 

 this heavy type of cover was replaced by lighter and less 

 clumsy ones. At first these were still made of thin 

 boards, covered with leather or cloth ; but as the art of 

 manufacturing paper became better understood, this 

 substance gradually replaced all others. 



For several centuries after the invention of the print- 

 ing-press the whole process of bookbinding was done by 

 hand. The sheets were folded by hand as they came 

 from the presses, sorted, and sewed together by hand. 

 The covers were made practically without the aid of 

 any machinery, so that frequently the reputation of a 

 bookbinder rested entirely upon his individual manual 

 dexterity. Artistic taste also entered into the estimate, 

 and upon a combination of these qualities rests the 

 fame of the early binders such as Grolier, Le Gascon, 

 Pasdeloup, Derome, and, later, the Englishman Roger 



