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LEFT ELECTRICAL MACHINE 489 ELECTRICAL MACHINE gates to the national convention. In most States, however, it is not obligatory upon the delegates to follow these in- structions. In the primary elections there is no law compelling publicity of campaign expenditures, and this again has tended to produce corrupt practices in party elections. The revelations made by the Congressional Investigating Com- mittee as to the money spent by the rival candidates for the Republican nomination in 1920 stimulated the de- mand for stricter State laws governing primary elections. In England there have been but few amendments to the excellent Corrupt Pi'actices Act of 1883, which limits the expenses of candidates and clearly ex- cludes all methods of intimidation, bribery, or any other means of improp- erly influencing the voter's choice. By Act of Parliament woman suffrage was granted in 1918, and in the elections held charged and the charge was collected by means of insulated metallic forks, while the negative electricity produced on the leather escaped to the ground. A modi- fication of this machine was that of Ed- ward Nairne, who used a glass cylinder, with insulated conductors on opposite sides. One conductor carried a leather cushion, and the other a row of metal points, while a silk apron covered the surface of the cylinder from the leather almost to the points. Positive electlncity was formed on the conductor carrying the points and negative electricity on that carrying the leather cushion, while the silk served to prevent the loss of the electric charge while the cylinder was passing from the rubber to the collecting points. All these types of frictional ma- chines have been rendered obsolete, how- ever, by the introduction of the so-called "influence machines," which operate by induction. Suppose a conducting body ELECTRIC ENGINE in December of that year women cast their votes for Members of the House of Commons. ELECTRICAL MACHINE, a machine for converting mechanical work, either by friction or by induction, into electric snergy. The earliest known form was 2onstructed about the middle of the 17th century by Otto von Guericke. It con- sisted of a ball of sulphur mounted on an axle which was rotated as rapidly as possible while the hand of the operator was pressed against the ball. The fric- tion of the hand upon the sulphur gen- erated electricity. Sir Isaac Newton replaced the sulphur ball with a glass globe, and later workers substituted woolen cloth or pieces of leather for the hand. In 1768, Jesse Ramsden con- structed the first plate electrical ma- chine, consisting of a glass disc, which was rotated rapidly between two leather rubbers. The glass became positively is brought near to an electrified sub- stance having a positive charge. Then negative electricity is attracted by the charged body, while positive electricity is repelled, and if the conductor be con- nected with the earth, the positive elec- tricity will escape, leaving the conductor charged with negative electricity. This is the underlying principle of the in- fluence machine. In the Topler machine, for instance, two glass discs are used, one of which is fixed, while the other will revolve. On the latter are fixed a num- ber of strips of tinfoil and, on the other, two so-called "field-plates," also made of tin-foil. A charge is given to one of the field plates, and then the movable plate is revolved. Let us suppose that the charge on the field plate is positive. Then as a tin-foil strip moves into place op- posite the field plate, negative electricity is attracted and positive electricity re- pelled. A brass wire brush makes con-