Electricity Notes.

Progress, Volume I, Issue 4, 1 February 1906, Page 79

Electricity Notes.

The lengths o f electric waves measured by Herz and named after him were found to be 150 ft. from the top pf one wave to the top of ibe next. The waves used by Marconi m telegraphy across the Atlanta Me much longer, being 6oc> It pr more. They travel at \hz same speed as. hgM al ihe lncrtchble and almosi inconceivable r*te of i?a pep mites p<r s«^<:oo<f B«^ 3 wav<* o^ /»ght jn«asur^s only a (<w nulUgntUs gf an inch.

The combination of oxygen and hydrogen, when a mixture of these gases is exploded, is believed to generate a large amount of electricity. The results are very irregular, probably owmg to the action of moisture. At jeast 10,000,000 molecules pf water vapour are termed for every pair of ions prpduced. The energy sm lire by the explosion js very great compared w>th the amount required ie ioim the ions so th»t <H?»r formation may only t>e a Secondaiy-

Electrically driven ploughs and farm machinery constructed by an Italian firm need for th< ir operation two paw* r cars stationed at each si4e of the field, between which are stretched cables attached to the plough, Electric current of about 500 volts is taken from a trolley line. The plough is pulled by the cables from one side of the field to the other, and when it reaches the end of the furrow >t stops automatically, current being cut off U can be run backw**d& pr forwards with ease

A broken Overhead trolley wire »s a Source ot danger, and rftgre than one devjce (or cutting off the current Arid so rendering the wir« harftUess has been suggest^ The latest invention {or this purpose is ntts<d to each section of the wir«, and consists of an ordinary connecting ear, hel^i ln its proper position by the strain on the trolley wire. Directly this tension is released, as by the breaking of the wire, the current is cut off from the broken section without any sparks whatever taused by short circu>ti

EtncrntCAt pumps it* coLLiERtu — §peakm% before the iVUnch«sC«r Geological md Mining Society recently Me G. K. HooghwinWt MIME, M.1.E.E., <t*pr?ssed the opinion that «h« pump destined to *up«rcede all others— and first <jf all steam-driven p u mps — was the electrically driven high-pressure centrifugal pump. This, he says, is an ideal mining pump, on account of ita various and valuable qualUes, including cheapness, compactness, strong construction, and absolmt security from break dcw n

Tht >!wtM»c>n dJ Ihe incandesctni tittirjc )amy Aas b«<?» £^6r3*ed by founding a Thomas A Edison medil which has been entrusted to th* American So^ty of EJectrica] Engin^rs The circulif issued by the Edison Mtdil Association announ<:^s that it is the intention tU*t the medal shall b« awarded each year to the graduating student who shall present the best thesis en some original subject from the universities and colleges oi the United States and Canada which have regular coupes in electrical engineering It is quite possible that if the Institute of Electrical Engineer ****• approached, the field c>i ihe cpmpetition rftsg^' br enJax^ed to embifctt i^denls oi New 2*a)ai>rf £-Ol)egcs and univeiiiUts

Two years agg (he use of windmill paw«r fgr generating «l«cUiaty was successfully tri<4 in Europe. At Hamburg, and near Leipsic, there are electrically driven plants which derive their power entirely from the wind. Considerable attention has lately been given to this question in the western districts of the United States. So great is the v*nrty there of home madt *i^d commercial w>ndr*>ll& that a special bulkon describing them ha^ Wen issued by the I>t£*j indent oi AgntuhuTt At Jus! ihe windmills, weit \c> generate electricity far fighting <fi? tarns and hom«s ; 5«( to-day a good many sj( them operate small electric motors. Tru: wvo^lmklls used are of th<? ordtoary types, buiU t<3 Uansmit the full pow^r q( the moving air <:ucr*nts to the generator located at the bottom of the structure. A single large windmill, of the home-made type or of modern commercial form, wilt, it is said, run a two, three, four, or even five horst -power motor.