Proceedings of the American Academy of Arts and Sciences. 

 Vol. XXXIX. No. 2. — July, 1903. 



CONTKIBUTIONS FROM THE JEFFERSON PHYSICAL LABORATORY, 



HARVARD COLLEGE, 



ON THE PROLONGATION OF SPECTRAL LINES. 



By Thkodoke Lyman. 



With a I'i.ate. 



Investigations on Light and Heat made or pttblisiied, wuolly or in pari, with Appropriations 



from the kumford fund. 



