Handbook for the use of electricians in the operation and care of electrical machinery and apparatus of the U. S. seacoast defenses .. (1904)
United States. War Dept · Washington, Govt. print. off. · leaf 206
DO 201. Cross=section of Iron=Pipe Conduit. … 202. Clay Conduit in CementMandrel. exactly fits the bore, preserves ths; mortar getting inside. The bottom of each 18-inch length duct is slightly curved upward, so that the joints may not interfere with the drawing in of the cable. (4) The manhole (fig. 203), about 34 by 3^ by 7feet deep inside,…
Electric machinery · Searchlights · Coast defenses
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
