MIRACLES OF SCIENCE 



Hopkins University has perfected a thermal couple 

 which, as a detector of heat, is more than ten times 

 as sensitive as the radiometer. Used in conjunction 

 with the 100-inch mirror of the new Mount Wilson 

 telescope, this instrument would detect the heat of 

 a candle sixty miles distant. It suggests interesting 

 new possibilities of investigations. Doubtless in time 

 extended observations will teach us important les- 

 sons about the nature of the various stars, as re- 

 corded by variations in radiation. Meantime, the 

 proof that this radiant-push exists and is everywhere 

 operative is in the highest degree interesting and 

 important. For an ether wave that pushes with such 

 force against anything with which it comes in con- 

 tact must be a factor in the distribution throughout 

 the universe not only of energy but of matter. 



Professor Svante Arrhenius, the famous Swedish 

 physicist, has estimated the size of a particle of mat- 

 ter which would be driven before the light waves, 

 as particles of dust are driven before the wind. He 

 believes that radiation pressure explains the phe- 

 nomena of the comet's tail, of the sun's corona, 

 and of the aurora borealis, the latter being due to 

 the activities of electrified particles driven to the 

 earth from the sun. Thus radiation is in a sense a 

 counterforce to gravitation. 



What gives the phenomenon chief interest from 

 the present standpoint, however, is that it shows the 

 tremendous energy of the atomic forces that send 

 out the ether waves. A molecule or atom vibrating 

 in such a way as to send off at the rate of many 

 billions per second, and at a speed of 186,000 miles 



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