Elegist, Elegiast, Elegiogʻrapher

writer of elegies. A El'ements, Chemical. ( Chem .) The simplest known constituents of chemical substances. Chemists regard as elements only those substances which have not been proved to be compounds; though there is reason to believe that some, perhaps many, of these are actually compounds, and may be proved to be so in the future, as supposed elements have been in the past. The elements are somewhat arbitrarily divided up into metals and non-metals, of which the former are far the larger cla . But no well marked line of demarcation separates these cla es, which seem to shade into each other on their border line. The non-metallic elements, as commonly cla ed, are thirteen in number, viz, Hydrogen, chlorine, bromine, iodine, fluorine, oxygen. sulphur, selenium, boron, nitrogen, phosphorus, carbon and silicon. Of these, however, hydrogen displays certain characteristics a imilating it with the metals. Many chemists at present entertain the view that all the elements are compounds of one fundamental elementary substance, while many others look for a reduction in the present list, which may come through the decomposing action of the electric furnace. The Greeks recognized four elements only: earth, air, fire, and water; the ancient Chinese five: earth, water, fire, wood, metal; the ancient Hindus five: earth, air, fire, water and ether. At present sixty-four are recognized, to which perhaps argon and helium will doubtle be added, with several others whose claims are not yet substantiated. For a list of the elements and their combining weights, see Атом. Elevators, or Lifts. ( Arch . ) Devices for lifting freight or pa engers from the ground to higher elevations, or for lowering them from higher to lower points. They consist of a closed car or open platform, raised by ropes or chains, or pushed up by a ram from below, steam or other power being employed for this purpose. The car moves between vertical rails of wood or metal, which hold it in place. Elevators, in some form or other, have been used from a remote period, being propelled by human, animal, or water power, but their extensive application to buildings dates only from about the year 1850. Their common employment has enabled buildings of great height to become common, and has greatly extended the area of habitation within city limits. Elevators are variously cla ed, in accordance Fig . 2864.-AUTOMATIC STOP FOR ELEVATOR. apart, and the cable taken up, the car being thus lifted On removal of the pre ure, the car descends by its own weight, drawing the sheaves together. In towers which po e high pre ure water service the cylindere may be connected directly with the mains; and in other cases artesian wells supply the nece ary water. When the pre ure is insufficient, water is pumped into storage tanks at the top of the building, a head being thus obtained, and in some instances additional force is obtained by the use of closed tanks partly filled with compre ed air. Where tanks are employed the same water may be used over and over again, the only lo being from evaporation.- Electric elevators are quite similar in principle to steam elevators, the only difference being in the kind of power and motor employed. The ascent and descent of the elevator are controlled by means of a rope which is connected with the moving apparatus, and which, in belt or power elevators, operates a belt shifter that is, a valve which cuts off the steam or water, or reverses the direction. A switch servee this purpose in electric elevators, making or breaking circuit, or reversing the current at will. The operating rope may be worked directly by hand, or indirectly through the use of a lever or hand wheel. Another important requisite of elevators is a safety device, to coutrol their speed, prevent their running beyond their limits, and to check a dangerous fall in case the cables break. To prevent overrunning, stop balls are employed on the operating rope, which act automatically in the case of neglect by the operator. In elevators run by drums or hydraulic pistons, the valve is closed automatically when the car has reached its maximum height or descent. To prevent a fall, grips are employed, which are brought into action by springs or levers actuated IMG:content-0103.png:[ocr errors][merged small] by the breaking of the cable, and which act upon the strips or rails guiding the car. If the car descend at dangerous speed, ball governors on the top of the car operate the safety grips, these balls opening sufficiently to do so when a certain speed is attained. Safety grips are of varied forms, the most common being wedges which squeeze the guide strips, or toothed dogs which cut into the strips, which, in this case, are made of wood. Of notable elevators may be named the steam elevators in the Washington Monument, 500 feet in length of travel; the hydraulic elevators of the Eiffel Tower, with 420 feet of travel and a speed of 400 feet a minute; and the hydraulic elevators in the station of the North Hudson County Railway Co., at Weehawken, N. J., which can lift 140 persons at a speed of 300 feet per minute. The elevator has become an indispensable adjunct to modern architectural methods, rendering po ible the habit of living in flats, now common in many crowded cities, and the use of office buildings reaching many stories into the air. Grain Elevators. The term elevator is also applied in this country to a structure of a different kind, the great buildings for the storage and easy handling of grain, in which it is often kept for months. Some of these elevators are capable of storing from 1,000,000 to 1,500,000 bushels of grain within their capacious walls. The largest of these exist at Chicago and Buffalo, cities through which pa es a large percentage of the grain of the U. S. The grain on being received at the elevator is examined and graded, the farmer or merchant being credited with so much grain of such quality, and grain of that quality being delivered from the elevator on his order. Elevators are usually built so as to permit easy acce of ve els, and have railways entering them from the street. The grain is carried into the elevator and delivered from it by the aid of a chain bucket, which receives its motion from an endle band pa ing over shafts in the upper part of the building, the engine and boiler being placed in an adjoining edifice. By this means vast quantities of grain can be handled at small expense, being taken in a continuous stream from the wagons and cars, and delivered in like manner directly to the hold of the ve el to be loaded. In New York floating elevators are frequently employed to transfer grain from barges directly to sea-going ve els. Within a recent period, experiments have been made in the employment of pneumatic tubes for handling cereals in bulk, by the use of which grain has been succe fully transferred from car to elevator and thence to ve el; the power being that of compre ed air, by means of which the grain is "pumped" from one point to another. In connection with this method of transport, low storage buildings, made of iron, take the place of the usual lofty elevators. This system has not been largely adopted.