Scientific Lectures. 129 



SCIENTIFIC LECTUKE.-IX. 



Oiq" THE PHOTOMETER. 



By Professor R. Ogdex Doremus. 



Prof. E. Ogden Doremus delivered the ninth lecture of the 

 scientific course before the American Institute on Friday evening, 

 January 22d, 1869, at Steinway Hall. He said : 



Ladies and Gentlemen — "In the beginning God created the heavens 

 and the earth, and they were without form and void ; and darkness 

 was upon the face of the profound." What pen shall describe, what 

 tongue shall tell, what human imagination conceive of that tide of 

 glory and splendor, which undulated throughout immensity when 

 God s^d, " Let light be," and light was ! Such is the most beautiful 

 and terse description oftered in that word of God on which the dying 

 Christian blesses the Almighty he can pillow his head, and the 

 burning martyr returns thanks if he can mingle its ashes with his 

 own ! To tell the story of the first light which dawned upon the 

 universe of God, is beyond the power of man. To tell indeed what 

 has been discovered concerning it would extend beyond the short 

 time allotted to a lecture. That light moves through space with the 

 immense velocity of nearly 200,000 miles in a second of time ; that 

 Avhen we look at the sun we gaze at the light that parted from it 

 minutes ago ; that when we look at the stars, no one is so near us 

 but that three and a quarter years have elapsed during the passage 

 of that mysterious influence ; and when we look up on such a beautiful 

 cloudless night as this evening, and see the magnificent scenery of 

 the heavens, that those worlds send us light which started on its 

 march long before we were born, and, in m.any cases, ages before our 

 race existed upon this world — such are the facts known to modern 

 science. And how shall I tell in the brief limits of a lecture of the 

 power we have, by clear transparent media, to compress these beams, 

 to concentrate these rays, so that we can gain information from the 

 distant realms of space ? Let us not forget the great Itali^ja, Galileo, 



[Inst.] 9 



