The Luther ore conveyer has met with con siderable sale in Germany. This consists of a series of rectangular sheet-iron pans, moving on roller bearings. It travels quite swiftly and is used for coal, ashes, sand, sugar, etc., as well as ore. When used for carrying coke, or any other material that tends to wear the metal pans, glass bottoms are employed, which give good satisfaction.
For lumber-mills and large wood-working plants a different style of conveyer is manu factured. The Schroeder Lumber Company's works at Milwaukee, Wis., afford a good ex ample, being equipped with a sort of traveling sidewalk, consisting of parallel planks attached at right angles to two malleable iron chain belts. At intervals a thick plank is inserted to keep in place the hard wood lumber that is piled on to this conveyer, which is really a strip of moving floor for transporting boards to another part of the works. For handling waste ends and kind ling, a small type of conveyer is used, fraying hoppers at intervals. Into one set of hoppers the machines that cut up the hard wood drop the end-pieces, etc. Into another set of hoppers the trimmings of soft wood are dropped, and both hard and soft wood are carried up an incline and dumped into an enormous hopper, where the hard and soft wood are kept separate and may be withdrawn from below as wanted for kindling or other purposes.
A conveyer has been devised for loading box cars, the loose material being introduced by a spout at the centre of the car, and carried by the conveyer to the ends, in such a manner that the ends are loaded high rip, avoiding waste. These are used on the Hocking Valley Rail way.
The belt conveyer is simply a long endless belt, supported at intervals by rollers or idlers, so shaped that they curve up the edges of the belt, enabling it to carry along material with out spilling off. The belts are sometimes made of leather, but more commonly of cotton duck, faced with rubber. Such conveyers are used in grain elevators, and for ashes, cement, chips, day, coal, concrete, earth, ore, oyster shells, tailings and the like. The storage tanks of grain elevators employ belt conveyers almost exclusively, the modern circular tanks having a belt gallery that runs across the tops of the tanks and connects them. The belts thus dis tribute the grain from the main elevator to the several tanks.
In handling ore, labor is often reduced by means of sorting conveyers, which are made to serve the purpose of sorting tables, at the same time that they serve to convey the ore. These
travel slowly, and men stationed at the sides examine the ore as it passes, breaking any pieces deemed too large for the process to which the ore is to be subjected. The large stone-crushing plants very commonly employ belt conveyers, as being the best adapted for handling' broken stone. While belt conveyers are used to some extent for handling coal and ashes, they are restricted in use to inclinations of about 20 degrees. For steeper work or direct elevation the bucket type of conveyer has to be employed. All the conveyers that operate with endless chains or belts normally deposit the material at the point where the chains or belts are curved over rollers or sprockets for return. For depos iting the material at points along the route, various forms of trippers are manufactured, according to the nature of the conveyer and of the material handled. For filling a conveyer en route there are also in use numerous styles of fillers, many of them being simply spouts lead ing from hoppers, and others specially designed for the work they are to do.
The type of conveyer used on a cableway is radically different from the foregoing. A wheeled carrier is slung on a supporting rope, usually a steel wire rope, and from this cater is hung is material to be conveyed_ To the carrier is attached a rope, and a conveyer engine at one end of the cableway pulls the load along to its destination. This is the system followed in coaling vessels at sea. The United States battleships are coaled in this manner dur ing rough weather, the coal being readily car ried aboard under these conditions at a rate of 20 tons an hour.
In excavating work, as the New York sub way and the Chicago drainage canal, this type of conveyer is in constant use, owing to its economical construction and portability. The system is employed for handling sand, at glass works, etc.; for discharging cargo from a vessel to a shore Where there is no wharf ; for carry ing material over rivers or rough land, as in new sections of country, where there are no good roads; for transporting the material used in building breakwaters and piers; in the build ing of dams and locks, and for a variety of purposes in connection with mines. A few con veyers have been built for permanent use, in which an overhead truss or bridge with a rail takes the place of the cableway.