. Popular electricity magazine in plain English. nd it is wound half-hourly by means of electricity. It isthe clock in. this country that mostnearly approaches perfection. Scien-tific officers of the government, regu-larly detailed for the duty, watch overit day and night, constantly correctingit by observations made from the sunand stars. Thus this clock in the great glasscase, though of itself it does not keeptime with the sun and stars and theearth, is made so accurate that even thescientists, who say that there is noclock in the world that is perfect, callits time correct. Strictly speakin
. Popular electricity magazine in plain English. nd it is wound half-hourly by means of electricity. It isthe clock in. this country that mostnearly approaches perfection. Scien-tific officers of the government, regu-larly detailed for the duty, watch overit day and night, constantly correctingit by observations made from the sunand stars. Thus this clock in the great glasscase, though of itself it does not keeptime with the sun and stars and theearth, is made so accurate that even thescientists, who say that there is noclock in the world that is perfect, callits time correct. Strictly speaking,we are assured, the only thing thatdoes keep time is the earth, change-lessly rotating through space. Butmathematicians and astronomers con-cede that the time of the big clock in-side the glass case comes nearenough. That means within somethousandths of a second. It is this almost perfect clock thaisets the standard time of this coun-try. The enclosure in which it si amisin the Observatory at Washington issurrounded by three walls with spaces. Corner of a Ducal Dining Room in London between. It rests on massive stone pil-lars that reach far into the earth. Thetemperature is so maintained that,should a human being step into theroom, the increase in temperature oc-casioned by this intrusion would beregistered on a thermostat of almostincredible delicacy. The corrections continually beingmade in this clocks time by reason ofthe astronomical observations arc seldom more than ten one-hundredths ofa second. They arc frequently lessthan five one-hundredths. Prom the almost perfect clock,which is in duplicate, wires pass to twotime sending clocks in another room o\the observatory, it is through thesethai time passes out to the one o\ the two lasl mentioned 1426 Popular Electricity and the Worlds Advance clocks is needed at any one time, butthere must be two to guard against ac-cident. If science cannot quite succeedin getting any clock to keep absolutelyaccurate time, it
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectelectri, bookyear1912
