ELECTRICITY

Science is still unable | Ele Eto _—_s definite answer to the question, | scal 3 is Electricity 7?" From the fact/| are: that, under certain conditions, it dows| E _ from one point to another, it has been | afo _ spoken of as the electric fluid, though it| F — no other are fluid except in | ing ) one i. It was wng con-| pro sidered Stans of energy, but recent/ of d investigations have disproved this theory, | lam and rather suggest that Electricity is/ gro:: the basis of every form of matter. are Ancient Greek philosophers knew that} car i; & piece of amber, when rubbed, po e ed | and the of attracting and then} Aft, repeting light bodies. Towards the close | arc: 4 the 16th century, Dr. Parker dis | and _ Govered that a large number of other/ of t Substances, including the diamond. gla , | cart _ @aulpbar, sealing-wax, and resin po e ed | that the same property. Later it was observed | The; that a flash of light accompanied by a/ and = pase Bape was obtained when | the ibed bodies were discharged, | desc { suggesting in mini at are the lightning | bon: the ma cad ig thunder. | wire, Machines were construc for the pro-| ther duction of Blectricity in larger quantities. | the Accylinder of gla , or a disc of plate-gla , | beat _ Was made to revolve against a cushion of | to ¢ feather coated with an amalgam of zinc or} the tin, and the charge of Electricity thus} may _ Generated was collected on a hollow metal} elec _ Cylinder mounted upon ao gla leg, and | can _ known as oS oheg conducior. Improve-| E ‘ ments ip frictional machines wero intro-| syst duced by Holtz and Wimshurst. trail ' ‘The next important development was} com i due to Volta, Profe or in the University | Blec of Pavia. He placed a cican shicet of | dyn: gine and another of copper in a ve e!| the | containing dilute sulphuric acid, and | stat i found that, when the two meta! plates | cont. Were connected by a aioe iene of | reco copper wire, a current of Electricity | pow flowed through the wire from the copper | case y to the zinc, and that the iatter| the: wasted away, while a fow bubbles} slun ‘of hydrogen gas collected on the former. | depe eeerenay nece ary to drive the current | elect through wire is due to tho chemical} a m Action of the — on the zinc. Sot In t _ Gfrangement own a8 @ cell. The| Blec “Copper strip, whence the current sterts| mou > the wire is called the posilice pole, | Mot and zinc strip the negative pole. Zinc | This 8nd platinum, or zinc and carbon, also| and form good combinations for cells. A | initi “Combination of two or more such cells is| wor! | ie experin Sa eactcevind by Faraday | the ae orm y Faraday | the fn 1830 before the Royal Scr fa 1903 y far-reaching results. A length | mou wire - ohagey ere times | cond By a hollow nder of wood, the ends | mets carried a Sed distance along the table, | cond ‘and wound into another coil over which | trici & Magnetic needle was suspended by a| in th st thread. When the demonstrator | to t ‘ipa & bar magnet into the hollow of| the the Grst coil, the needle was seen to| curr Osciliate. While the magnet remained | thirc _ Bt rest within the coil the needle occupied | two. its normal —. The same results followed if magnet was fixed and the| for "coll moved forward and backward over it, | and — defection of the needle increasing as | accu ae Movements of the coil became more | lead ben The experiment proved that| oxid _ Se movement of a coil of wire in a mag- | aulp! “Rete Geld—that is, the verge around | curr; ® magnet within which the magnetic! give. a *" SSS ews Wee wee VS eee ewes tl he wire, and that the strength of the | w aced current increased with the rapidity | re the motion. The apparatus used | th tained all the e entials of the modern | H amo, in which the current is induced | ca causing coils of wire to revolve very | pl “tT iu @ magnetic field. By thie means | th ty is produced on a commercial | th e, and electric lighting and locomotion | co rendered practicable. se [s. 132]