The Mechanical Handling and Storing of Material

THE HANDLING OF MATERIAL BY PNEUMATIC MEANS 223 which in its turn revolves the main portion of the trap slowly. The wheel, with its six compartments, is 16 in. diameter, and 8 in. wide inside. Another small pneumatic installation is at a mill at Sowerby Bridge, and was erected by Messrs R. Boby, Ltd., on the Topf system. The pipe is 4 in. diameter, the total length being 360 ft., and the lift is about 10 ft. The plant had a guaranteed capacity of 10 tons per hour, but it has easily dealt with 14 tons, with a consumption of 25 H.P. Power Consumed by Plants of the Latest Type.—The most up-to-date plants now made consume a little under 2 H.P. per ton of grain handled per hour, to an average height, and with an average length of piping. Ihe power consumption is, however, still very excessive for the actual conveying work performed, and if pneumatic elevators are largely used in spite of this fact, as well as the enormous initial cost, it must be put down to the extreme flexibility of their application to unloading grain vessels, their clean working, and the saving of all hand labour for trimming, as the suction nozzle can be brought into all nooks and corners, and almost literally every grain can be collected out of the hold. The Pneumatic Removal of Ashes from Boiler-Houses.—Labour-saving devices for this purpose are one of the latest additions to the ever-increasing number of such appliances. In small boiler plants the ashes are easily handled more 01 less mechanically by a skip-hoist or elevator leading to an elevated receptacle to hold the ashes in suspension for loading into trucks or carts by gravity. Such equipments are satisfactory and inexpensive. The upkeep, though proportionately high, is not laige in amount. Generally speaking, mechanical conveyors for ashes are unsuitable unless very