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Show HOW TO PICKLE STEEL. ' . 1 The DicHina- of structural steel was probabfy flrst done in this country In connection with the steel I flooring of the Williamsburg bridge. In .New York City. The 'iflcatlons for the twelve-Jnch channel, on which the paving blocks a carried requfredhem to be cleaned 4nd pamted with pure Unseed oil while tin hot from the rolls. When it came time' to execute the work these specifications specifi-cations were changed so as to permit I the matal to be cleaned In pickling baths, which has long been done to a ' ' . - ' ' 1 considerable extent In Europe. In the . . case of the channels for the Williams- ' burg bridge the shapes were first boiled in a 10 per cent solution of caustic soda to take off greasend, were then rinsed In boiling water. Afterward they were dipped Into a boiling 10 per cent solution of ulphuric acid until all the oxide was remove. After being rinsed la boiling water thry were dipped into a boiling 10 per cent eolation of carbonate of soda to -free them from any trace of acid, finally fi-nally thsy .s-tre rinsed In boiling water, dried over steam pipes and then treated by the Eabln process of enameling. En- . jlneerins; Record. - . . , ' . -. - ' |