A WONDERFUL INVENTION.

Dunstan Times, Issue 3381, 4 July 1927, Page 2

A WONDERFUL INVENTION.

RUNNING A BATTLESHIP WITH A SHADOW. A passing shadow or a dewdrop may now turn'on the lights of a city, start or stop a railroad train, or manoeuvre a battle-ship. These results, and others quite as marvellous, are brought about by a. device for controlling electric power, so sensitive that it can be operated by the mere approach of the human hand. Its inventor is Dr D. D. Knowles, research engineer, of the* Westinghouse 'Electric and Manufacturing Company. To illustrate- the sensitiveness of this device, wc are told in a press bulletin issed by the Westmghouse News Service, a watch is laid upon a- plush cover on a small table. 'Though the watch is in no way connected with an electric circuit, any attempt to pick it up results in ringing a-bell and lighting a light. It is not necessary to touch the watch —the alarm goes off as soon as the hand comes within a- few inches of it. The same thing hapens when attempts are made to touch a picture or pick up silverware from a plate. The alarm is- also sounded when water is dropped from an eyedropper upon two small parallel wires, and also when the flame of a match is held beneath the wires.

By connecting a tiny photoelectric tube in the circuit, the device is made sensitive to light and operates when the window shade is raised and lowered or when the shadow of the hand is cast upon it. The device causing these effects is a tube which closely resembles a. radio tube in size and appearance, but which lights up with a pinkish glow whenever it operates. It is known as the Knowles Grid-Glow Tube. Mr Knowles, a graduate of Perdue University. is but 28 years old. He explains : “This tube is a relay, that is to say, it is a device which is operated by a small current and controls a much larger one. The ordinary relays used in electrical engineering control a. current iO,OU(J times greater than the current controlling them. But my tube has an amplifying power or around one hundred million, and it is probably by far the most sensitive thing of the kind ever devised.

The energy required to operate it is about one-billionth of a watt, or about one-fortieth of the amount of energy exerted by a lly crawling vertically upward one inch in one second. This infiwitesimailly small amount of energy is sufficient to start flowing through the tube a current that will close or open a switch handling upward of 2b amperes; and this in turn is ample for controlling almost any operation. Thus jl is quite possible by the'use of this relay for a passing shadow or a dewdrop to turn on the lights of a city, start or stop a railroad train, or manoeuvre a battle-ship. “One of the interesting features of this device is that it consumes no measurable amount of energy, except w heu Actually operating, and suffers practically no- deterioration. It can be set up and, kept ready tor operation indefinitely without expense; and after it operates, it returns to its original state prepared for the next occasion. Its operating speed is 1-120-second on ordinary alternating current, and it can be operated continuously for several years before wearing out. It is very simple in construction and can be manufactured in quantity at a small cost.

•‘lts chief application will be in elec trical engineering, because the tendency is now in the direction of automat e, sene-automatic, and supervisory control for electrical circuits, and for this purpose relays of every description are needed. ■‘ln addition, however, it can bo used to protect valuable exhibits in stores, museums, and p.cture galleries; turn lights on at night and off at daybreak; give advance warning "of thunderstorms: guard gas and oil stoves and furnaces by turning off the fuel sup-

ply in ease the flame is accidentally extinguished ; count people, automobiles, or products pass ng given points; send out alarms in case intruders enter doors, windows, or pass through ha-lbs or stairways; provide a very delicate fire alarm: and control the temperature of ovens, furnaces, etc. AMERICA S POOR PEOPLE. British newspaper comment on America’s wealth has drawn the following interesting comment from Mr John M. Meloan, Superintendent of Public Printing for Kentucky. Me savs:

! read in your papers that the people of the United States are “fairly rolling in wealth, and are making more money than they know what to do with,” or words to that effect. 1 understand this only expresses the prevailing opinion throughout the British ! slancts. We have a saying in this country that "the grass always looks greener in the other fellow’s yard.” Our English cousins apparently suffer from the same optical illusion. . The Treasury reports show that 82 per cent, of the people of the United Slates pay no income tax. A “single” man to pay income tax must have an income of ldOOdols (€300) annually, and a man of family must have an income of ‘ilOtkloU (£oU0). Therefore, s 2 per cent, arc exempt from this tax. inasmuch as they do not have that much income.

We have some rich people, of course, ay shown by the following paragraph: ".More than 9d per cent, of the income tax collections are paid by twen-ty-nine hundredths of one per cent, of the population. This is the same as saying that 2!) persons out of 10,000 par lid per cent, of the income taxes.”

But the idea abroad that the whole people of the United states are “rolling in wealth” is not true in any sense. I met a fine Englishman on the train tlie other day. He had been touring this country. He said “] like it. but it seems to me that you have an enormous populaiou of poor people, judging by those I have seen gathered at the smaller .stations along the way, with apparently nothing id do except to watch the trains go by; their dress does not by any means indicate general prosperity.” America has all the problems to solve that England lias. It has its army of unemployed, and a much greater army employed in pursuits, notably farming, which do not yield an income .su/ncient for a com for table livelihood. So get it out of the minds of the English people that America is a land (lowing with milk and honey and money. It will help them, and might save many of them the cost of a trip across the seas in order to become disillusioned.