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ONE of the vessels around which an acute political we can scarcely call it economic controversy has raged in America for some time is the “Corozal,” an extremely powerful bucket dredger which has been built by Messrs. Wm. Simons&Company (Limited), of Renfrew, Scotland, to the order of the United States Government, for carrying out some of the most arduous underwater cutting to be done in connection with the Panama Canal. The vessel has a hopper capacity of 1,200 tons of dredgings and the bucket-ladder is designed for dredging up to a depth of 50 feet. It is propelled at a speed of 10 knots per hour by two sets of triple-expansion, surface-condensing engines, supplied with steam from two cylindrical, multitubular boilers, constructed to .Lloyd's requirements for a working pressure of 180 -pounds per square inch. A complete outfit of the most modern auxiliary machinery is provided in the engine room, including independent air pumps, circulating pumps, feed pumps, feed heater and filter, etc. The dredging gear is of the most massive description and is arranged to give three speeds of buckets to suit the various kinds of material to be dealt with. The dredging gear can be driven by either of the main propelling engines. Two sets of buckets are provided, one of 54 cubic feet capacity for dredging soft material and one of 35 cubic feet capacity for dredging stiff clay. The bucket ladder is a steel girder of exceptional strength and an idea of the great strength of the bucket chain may be conveyed by the statement that the ladder with its chain of buckets, links and pins, weighs upward of 240 tons. The upper end of the bucket ladder is supported on an independent pivot shaft and the lower end is controlled by powerful steel wire-rope tackle and independent steam hoist gear, which is designed for raising the latter at a speed of 10 feet per minute. Steam maneuvering winches are fitted at bow and stern, each driven by independent, two-cylinder engines, and each barrel is fitted with friction clutch and brake, to enable the mooring chains to work independently of each other, or simultaneously, as may be required. Shoots are provided for loading into the vessel's own hopper, also overboard shoots controlled by independent steam winches, for loading into barges alongside. The hopper doors are controlled by independent hydraulic gear. This dredger, “Corozal/' w"s launched on the Clyde in September and she is to undergo severe tests before being despatched on her voyage round South America to the western end of the canal. Before leaving British waters, she will be tested, first in lifting sand and mud from the bottom of the Gareloch, off Helensburgh, and, afterward, she will be taken back to Renfrew where the buckets will be changed, and subsequently she will be sent to Belfast and tested in the (hard clay of the Musgrave Channel. The dredger was constructed to Lloyd's full requirements and Mr. T. M. Post and Mr. A. V. B. Candler have superintended the construction of the dredger on behalf of the United States Government for the Panama service.
