MECHANICAL SPIDERS

Wairarapa Times-Age, 3 June 1940, Page 8

MECHANICAL SPIDERS

STEEL WEB ACROSS HOOGHLY. NEW BRIDGE IN INDIA. The £1,600,000 Howrath bridge now being built by British engineers at Calcutta carries the third largest cantilever span—l,soo feet —in the world, only the Forth bridge and the Quebec bridge have larger. The two “long-arm-ed men,” or creeper cranes, which will be largely responsible for the building of the steelwork, will steadily piece the gigantic structure together, starting from opposite banks of the river. In doing so they will climb higher than the dome of St Paul's; travel at the rate of a foot a minute; and handle .loads of 60 tons. At the end of their task, when the two arms of the bridge are at the point of meeting over the Hooghly river, the cranes, which with their “cradles” weigh 765 tons each, will then dismantle one another.

Foundations have already been laid for the two great towers and anchorages to support the central span, and work has now begun on the actual steelwork forming the 25.000-ton superstructure. Indian labour and overseers, under a staff of British engineers and foremen, arc carrying out the whole of the work. In building the foundations of the tower on the Calcutta side of the river, compressed air at a pressure of 40 pounds to the square inch had to be used and, owing to the intense heat and humidity, the men could only work for short periods. This arduous initial task having been successfully completed, the creeper cranes are now preparing for their long climb, on which they will travel ahead, like monster spiders, on the steel web they themselves have made.