CONSTRUCTION OF XEW READING -ROOM, &C. 1 1 



" The Catalogue tables, with shelves under, and air-dis- 

 tributing tubes between, are ranged in two concentric circles 

 around the central superintendent's enclosure or raised plat- 



! form, the latter being fitted with tables, ticket-boxes, and 

 with dwarf partitions surmounted by glass screens, dividing 



I a passage leading to the smToundiug libraries. The pedestals 

 of the tables form tubes communicating with the aii'-chamber 

 below, which is 6 feet high, and occupies the whole ai-ea of 

 the Reading-room. It is fitted with hot-water pipes, arranged 

 in radiating lines. The supply of fresh air is obtiiined from 



I a shaft GO feet high, built on the north side of the north 

 wing about 300 feet distant, communicating with a tunnel 

 or sub-way, which has branches or 'loop-lines' fitted with 

 valves for diverting the current either wholly through the 

 heating apparatus, or through the cold-air flues, or partly 

 through either, as occasion may require. The air-channels 

 are of sufficient capacity to admit a supply of fresh air for 

 500 persons at the rate of 10 cubic feet .per minute, and at a 

 velocity not exceeding 1 '0 foot per second. For summer venti- 

 lation steam-pipes, placed at the summit of the roofs and 

 dome, will be heated, and extract the foul air when the exter- 

 nal and internal tempei*atm-e is unfavom-able for the purpose. 



''The arrangement of the presses is throughout peculiar. 

 It is calculated that the shelves within the Dome-room will 

 contain 80,000 volumes. Two lifts are placed at convenient 



j stations for the purpose of raising the books to the level of 

 the several gallery floors. The bookcases are of novel and 

 simple construction, the uprights or standards being formed 

 of malleable iron galvanized and framed together, having 

 fillets of beech inserted between the iron to receive the brass 

 pins upon which the shelves rest. The framework of the 

 book-cases forms the support for the iron perforated floors 

 of the gallery avenues, and which are generally 8 feet wide, 

 the central 6 feet being appropriated to the perforated floor, 

 and the remainder being a clear space between the back of 

 the books and the flooring, by which contrivance the light 

 from the skylights (in all cases extending to the full width 



