The Birmingham age-herald., 1908-01-26
THE WIDTH IF 4
 RAY OF LIGHT About Million and a Half Make
 a Meter SAYS PROF. MICHELSON Was Awarded Nobel Prize-Achieve- ments In Optical spectroscopics. Possibilities of Measure
 ment By Light Waves.
SAYS PROF. MICHELSON

Did you know that the yardsticls with which you raise your windows, the tape you throw about your should CTS, the ruler that came in contact with your toughened palm in school days, all are supposed to be exactly correct in accordance with a piece of metal over in France, with two scratches on it. wrapped in a cloth and sealed up in vault 80 feet under the ground? is the question asked by the Boston Herald
 Didn't know that?
 Did you know that every 10 years an international committee on weights and measures goes over to Paris, and with great solemnity unseals that un- derground vault, gently unwraps the piece of metal with the scratches on it, gazing upon the fetish in awed silence, and then compares with it lot of copies to see that they are correct within one twentieth -millionth of an inch?
 Never heard that before?
 Measuring Waves of Light.
 Did you know that scientists found that the old style of measuring, by which they could tell the size of thing within one twentieth-t ousandth of an inch, was so fearfully antiquated and inadequate, that they had to go experimenting for a way of measuring that was really somewhere near the mark?
 And that after while Prof. Albert Abraham Nicholson, formerly of Clark university. in Worcester, and now head of the department of physics in Chicago university, found out that a wave of light is about-he couldn't be exact more is the pity-is about one fifty -thousandth of an inch long, and that by stringing 100000 of 2,0o0,000 light waves together, side by side, ac- cording to their color, he could get a meter?
 Surely you must have heard of that?
 Isn't it about time to find out wheth- CT that yard of broadcloth you just bought is exact. whether you didn't get cheated to the extent of three or four light rays? Or perhaps you aren't quite as tall as you thought you were. If so, it looks as if you'd have to wait until the next time they open up that sealed vault and unwrap the standard meter. They only do that once every 10 years. L.,
 Professor Mich olson was last month awarded the Nobel prize for achieve ment in optical spectroscopics, and ms discovery of the possibilities of meas urement by the use of light rays III ether was the most potent factor Tn ms winning of the prize. He has just re- turned from Sweden, where the nm mense medal and the $37,o0O were awarded him, and describes hls experi- ments in measurement.
 He says:
 Need of Exactness.
 For scientific purposes. it is neces- sary that there shall be some way or determining with exactness the lengtn of the standard meter. Everything that we measure, whether 1t be planet or a yard of gingham, is measured ac- cording to that standard meter. l ma that there are few people who kno" anything about the standard meter.
 Ask the average man why yard IS a. yard, and he will say, Why IS 1oot a foot? Why, because,
 ..In the old days science would pe satisfied with a measurement thae caine within one twenty tn housandth part or an ;nch hut that would never do now adays when we can measure oo"h eo one twenty -millionth of an men.
 "conseouently 1t was necessary to oa+ ot some method by which the standard could be determined With tne ,,t,,,os+ nrecision. Various methods were +ried and there was one German pro lessor who experimented with the iisnI rays. but he did not succeed Tn set,ins closer to exactness than o.heis M got with pendulum vibrations anu ,saoh ustio experiments along various lines,
 arnrnX1mate reSuiLS. ..T aid moi start out deliberately 10 ma +ha 1enoth of light waves and apply tnat ;r determining the standard meter. iho discovery came while l was worhiiie on another problem. l wanted to aseei 'a,., .,.a ..uhatber the ether which surrounds the earth Is stationary, the earth ro.a'i,s throueb it. or whether 1t moved with the earth" ,,..o.,,i
 Everything Makes Difference.
 .rIot to YOU. perhaps, but everytnlns which has to do with the constructor ol matter makes a difference to the phys- ioist He wants to know these tnlnss' not hecause he wants to operate a mill or conduct an electric light plant put pc cause he believes that everything Ill tne world is worth knowing.
 'To conduct the experiment on tne other. | consisted of a piece of convex glass OH a flat surface. Under this glass were varying thickness of air, graduating to zero at the point where the glass touched the flat surface. The light shining through inc glass produced on the surface beneath if rings of light graduating in size ac- cording to the thickness of the atmos- phere under the glass.
 ..By moving this glass, increasing ana decreasing the quantity of air beneath the glass the rings were separated or con centrated. Without going too much into technicalities, it was in this way that discovered the length of light wave ana conceived the proper way of measuring standard meter. The waves or different kinds of light have various lengths, but speaking generally, light wave is about one ffty-thousanth of an inch long, It takes from 100000 to 100000 light waves to make meter, depending upon the color of the light.
 And after you have them all added up you simply know that meter is meter!"
 '.Thats all, but, personally. I was glad to find it out.'
 How Adam Was Punished.