ELECTRICAL INDUSTRY — SMITH 207 



ning its every step in the design, construction, and operation of 

 electrical apparatus has been guided by computation. In fact, the 

 electrical engineer has invented several mathematical tools to serve 

 his purposes, such as the complex quantity and symmetrical com- 

 ponents. He has even placed his mathematics on a mechanical basis, 

 such as that amazing creation, the calculating board. 



Pure mathematical concepts have given birth to many electrical 

 devices. Particularly has this been true of relays for the protection 

 of transmission lines and terminal equipment. A conspicuous recent 

 example is a new, simplified pilot-wire relay that greatly extends 

 the practical field of this type of relaying. This relay was conceived 

 directly from the mathematical conception of positive, negative, and 

 zero-sequence components of alternating currents. 



AS TO THE FUTURE 



We know so little about nature's basic underlying principles that 

 it is incredible that anyone should think that our knowledge of 

 natural laws is anything but exceedingly small when compared with 

 the vast amount that is listed in the unknown column. This alone 

 should be encouraging, for if we can accomplish all that we have 

 with such a poor understanding, it is reasonable to expect vastly 

 better results as we obtain more basic knowledge. 



While our human limitations may prevent us from seeing very 

 far into the future, present developments give us some idea of future 

 trends and in what fields expansions are likely to occur. 



In the processing industries, electricity will probably assume an 

 increasingly important role in the way of metering, regulating, and 

 controlling numerous phases of new as well as existing processes. 

 Recent improvements in electric furnaces and their controls, including 

 the control of the atmosphere inside of the furnace as well, indicate 

 various possibilities in this field. For instance, heat treatment of steel 

 sheets for automobiles by continuous processes in less than 15 min- 

 utes has been accomplished. In the presence of highly purified at- 

 mospheres, various steels and alloys can now be bright-annealed. In 

 controlled-atmosphere furnaces, dies can be heat-treated without 

 oxidation or carburization, thus eliminating subsequent grinding. 



In the broad field of air conditioning, electricity will play an im- 

 portant part, not only in applications requiring power but in the 

 processing and treatment of the air itself. Electrical means are now 

 available for cleaning and sterilizing air. These new aids in air 

 conditioning, coupled with the available services of heating, cooling, 

 and humidity control, make it possible to improve man's living con- 

 ditions so profoundly that he may live in a clean spring or fall 

 atmosphere all the year around in any locality. 



