. History of the Panama canal; its construction and builders . iiar«nnnnt;ui»r«mntanu»»nn«tnr«ii»i 77 *L. 1. Types of drill bits. 2. Vertical drill in operation. 3. and 4. Longitudinal section of Leyner-Ingersoll-Rand drills. (Drilling equipment on the canal furnished by the Ingersoll-Rand Company of New York.)

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Keywords: ., bookcentury1900, bookdecade1910, bookidhistoryofpan, bookyear1915