Fred T. Hodgson · Frederick J. Drake and Co. · leaf 463
are never placedso near the surface that they have not at least one ortwo inches protective covering. The steel so disposedis able to take up the tensile stresses which may be HOW TO USE THEM 459 induced in the column by eccentric loading, lateralshock3 wind pressure, and the pull of belting.… … J?ig. 7. -Rairborne System of Erecting Columns. in these boxes, and adjusted by gauges to within one ortwo inches of the sides. The concrete is laid andrammed, about six inches at a time, with small handrammers. The open side of the box is built up bybattens fitting into grooves in the permanent…
