12 CONSTRUCTION OF NEW KEADING-ROOM, &C. 



of the avenues) is thrown down the back of the books on 

 each story, so that the lettering may be easily discerned 

 throughout the book ranges. 



"The shelves are formed of iron galvanized plates, edged 

 with wainscot and covered with russet hide leather, and 

 having a book-fall attached. They are fitted at each end 

 with galvanized iron leather covered, and wadded pads placed 

 next the skeleton bookcase framing, to prevent injury to the 

 binding when the books are taken out or replaced. Between 

 these pads the skeleton framing of the cases forms an 

 aperture by which a eun-ent of air may pass and ventilation . 

 be kept up throughout. The shelves rest upon brass pins, j 

 the holes for which are pierced at three-quarters of an inch ; 

 apart from centre to centre ; but by a contrivance in cranking 

 the shaft of the pin, which may be turned upwards or down- i 

 wards, this interval is practically halved, and the position of | 

 the shelves may be altered three-eighths of an inch at a time. 

 There are 2,750,0i)0 of these holes! 



"In all cases, except against the external walls, the book- 

 cases are double, the books being placed on both sides, a 

 lattice of iron-\vork being fixed for their longitudinal separa- 

 tion. Thus, throughout the whole interior of the new build- 

 ing there are no walls, the division being in all cases formed 

 of a double range of books, fore-edge to fore-edge. The only 

 exception is at the shelving provided for newspapers, a single 

 range of wliich necessarily occupies the space of two ranges 

 of books. Three thousand superficial feet of cases are jDro- 

 vided for newspapers. 



" For convenience of access to the galleries, the staircases 

 have been placed so that, throughout the building, they are 

 within 40 feet of each other. The building contains 3 miles 

 lineal of bookcases, 8 feet high; assuming them all to be 

 spaced for the averaged octavo book size, the entire ranges 

 form 25 miles of shelves. Assuming the shelves to be filled 

 with books, of paper of average thickness, the leaves placed 

 edge to edge would extend about 25,000 miles, or more than 

 three times the diameter of the globe ! 



