Handbook of mechanical and electrical cost data, giving shipping weights, capacities, outputs, and net prices of machines and apparatus, and detailed costs of installation, maintenance, depreciation and operation, together with many principles and data relating to engineering economics (1918)
Gillette, Halbert Powers, 1869-, Dana, Richard Turner, 1876-1928, joint author · New York, McGraw-Hill · leaf 1021
e set in each wall between conduit runs on a level with eachlayer of ducts and set as nearly as practicable at the central point. The walls of all concrete vaults .shall be 6 ins. thick. The con-crete in the roof and floor .shall be thoroughly tamped. The con-crete in the walls .shall be uniformly… … ^JT Fig. 16. Vault size 8 to be used on runs of 13 to 24 ducts ofconduit when intersected. I6ll0v, ^ |1iOmi6i-
