The Bridgeport evening farmer., 1912-12-19
way from. .it .to .the sever. it .is pos-

away from it to the sewer. it is. pog-
 sible to grasp this idea by noting the
 current acts physically like one cOne
 tiIluous piece of material; such as a
 hoop- p-er an endless 5chain, one part of
 which will not move unless the whole
 of St moves. You cannot reVolye. one
 part of hoop without 4revolving the
 whole hoop. You, cannot. move, one
 part of an endless chain with out nov
 ing the whole. chain: In teIegraphing
 from New York to Chicago the action
 of electric current fs' s'apfeoisely silnf-
 lar to what it would be if you had a
 back, and you pulled upon it in terrz
 mittently to make the dots and dash
 es. Only instead of pulling on the
 chain you break and close the elec-
 trtc circuit. This can be done at any
 point aIongs the line, and, the effect
 Is apparent at any Other% place 7Or. at Sometimes the return part of the
 chain is by second electric wire, and
 sometimes the return is made through
 the earth. When the circuit is brok-- en at any point on the line the cur
 rent stops everywhere to start again
 when the break isz closed. Ss But>g how
 does the current in New.s York know that the circuit is broken in .Chicagoia. This brings to of the really
 remarkable facts about: electric cur.
 rent. It travels at the rate of 200.-s eUeak UUe es see Umii gheadv ai thls I distance R which is longer than any electric cir
 cult that has ever been used. So an
 electric current stops in less than a
 second if the circuit is broken any where within. 100000 miles of where the current is generated.
 We have said that an electric gen
 orator of ten horse power capacity run by ten horse power engine will transform ten horse power of me- chanica1 energy into ten horse power, tricfty with practically. no loss. This is true of a direct current generator,
 but in alternating current genera tor larger carrying capacity is re- ouired for the following reason. E1ec- tric power. Is the product of the vol une of current -(amperes01 and the pressure at which 1t flows (volts) just as the energy with which water flows out of a pipe is the result of the vol ume of water. and se the pressure at which it is flowing; The product of When the product is 1000 (1O0 volts x 10 amperes, or 10 volts x 100 arn- peres, for instance) it is called one kilowatt. In an alternating current the ann peres; and volts 're- verse their direction with marvellous rapidity, but: not always at. the same a motor which is being run by the | generator slightly before the volts or pressure. In that case the annperes I with mo voltage behind them are. idle I s nd do not iproduee4 any power. n But | the generator sSfhe motors and. the transmission lines, in fact all parts of tRe5aSySISIf1- I1S4Re-: COs g3e I11dOS= large enough to. carry. all of. the amperes, f whether they are accompanied by l volts and therefore produce power or | not. The idea can be best expressed | by a sinifIe: Imagine a man in abusi- ness: on borrowed capital who expects | a certain percentage aaEear | on the comm odity he sells providing | he sells it. promptly. Supposing he | cannot seIl:it promptlXc he has to pay interest on the capital invested in his stock: This, cuts down his net profits The fai1Wre of the pressure Ivolts) to of current .(amperes) cuts | down the amount of power delivered | by the machine in precisely the same | profits of: the. business man. If the 1 volts come a little bit later or earlier r than the amperes so thai 20 per cent. of flie amperes are not accom- panied r by volts this reduction is go per cent. and the r41aeffine;' or system, is said i. tor have only 80 per cent. power, fac tor. Therefore ak ygeneratprs with, so | per cent. power factor would have to be- big enough to transnlit the cur rent corresponding, to 12A horse [ 3ower in order to transform all the power from a ten horse power en- zine. Twenty per- cent. of the 121k | h orse power capacity, +or-- 2;1A horse-I power, Is sielI e. &ea pactty. The remain ing ten horse power are transformed. laIeS nn te eGoaeh te @ Rehg horse eae
 3ower, succeeds in transrnifting the full -outspiIit of fttfie engine. running if ten horse power.