Arizona republican., 1912-12-22
 Simple Explanations of Electrical Facts

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 Whenever you ask an electrical engineer a question he seizes pad and. draws a picture. This is get ting the cart before the horse The picture is a graphic representation of an idea. You have to comprehend the idea before you can grasp the significance of the picture.
 Electricity is far more definite science than that of steam power. The public has learned from constant repetition that about go per cent of the energy liberated by burning coal to run steam engine is wasted. In an electrical machine the waste is far less and the amount of energy that is generated can be measured far more accurately
 Electric generators are machines to transform mechanical power into electrical power. In other words, they generate electric current when driven by mechanical power They are run by steam engines. turbines, gas engines or some other form of mechanical power called prime nov CTS" The generator is constructed
 
 teal power that the prime mover rum hing it supplies. A generator run by a ten-horse power engine, for in stance, will transform ten horse power of energy, less small per centage (about 10 per cenD lost in the process. Electrical engineers don't usually say that generator transforms ten horse power Their 
 kilowatt which is equal to one and third horse power So they say that the generator transforms seven and half kilowatts. which is the equivalent to ten horse power Why should this change in nomenclature to any more confusing than to say that one inch is equal to two and a half centimeters?
 Mention the action of electric cur rent to a neophyte, and he immedi- ately assumes look of blank per plexity. Yet the fundamental facts about electric current are extremely simple. An electric current will not move unless it can move in com plete circuit, and get back where it came from. This is why it is safer fer d man handling an electric cur rent to work with one hand behind his back. He is then not likely to touch it in two places and thus com plete q circuit through himself. Elec- Iric current may be said to have ex- actIy the same sort of intelligence as a child playing puss-i -the-corner. The child will not leave the corner ! il occupies until it sees a corner free for il to go to- By likening the electric circuit to the piping system which leads the water to a wash ba- 1 sin and away from it to the sewer. l it is possible to grasp this idea by noting the difference in the action of electric current and of the water. ] In the case of ee ctricity, if you open 1 the faucet the electricity will flow only if the discharge pipe is free all the way. and il has the power of finding this out instantly even if the l obstruction in the discharge pipe is very far away. In other words an ! electric current acts psysically like 1 one continuous piece of material, 1 such as q hoop or an endless chain, | one part of which will not move un- l less the whole of it moves. You cannot reVOlVe one part of a hoop l without revolving the whole hoop. l You cannot move one part of an end | less chain without moving the whole i chain In telegraphin from New York to Chicago the action of electric | current is precisely similar to what it would be if you had long chain l reaching this distance and back, and you pulled upon il intermittently to make the dots and dashes. Only in stead of pulling on the chain you break and close the electric circuit. 1 This can be done at any point along the line, and the effect is apparent at any other place or at any number of places simultaneously Sometimes the return part of the chain is by a second electric wire, and sometimes the return is made through the earth. When the circuit is broken at any point on the line the current stops everywhere, to start again when the break is closed. But how does the current in New York know that the circuit is broken in Chicago? This brings is to one of the really re- markable facts about electric current. It travels at the rate Of 100000 miles a second, and can, so to speak, see ahead" this distance which is longer than any electric circuit that has ever been used So an electric current stops in less than a second if the circuit is broken anywhere within 100000 miles of where the current is generated. We have said that an electric gen. orator of ten horse power capacity run by a ten horse power engine will transform ten and a half kilo watts, of electricity with practically no loss. This is true of direct cur rent generator, but in an alternating current generator larger carrying cap acitv is required for the following reason Electric power is the pro- duct of the volume of current (am- peres) and the pressure at which it i flows (volts) just as the energy with which water flows out of a pipe is