606 PROCEEDINGS OF THE AMERICAN ACADEMY 



with success, and has got as low as wave length 900 tenth-meters, 

 Schumauu's estimated limit being 1000. The latter worked entirely 

 with the spectra of gases, and stated that he could not go below wave 

 length 1600 for metals." 



Professor George E. Hale states that the spectro-heliograph, in the 

 construction of which he has been aided by a grant from the Rumford 

 Fund, is approaching completion. He writes that " devices have been 

 introduced whereby photographs of prominences or faculae can be taken 

 simultaneously in two different lines of the spectrum. In the case of 

 eruptive prominences the comparison of photographs made in this way 

 may prove to be instructive." 



Professor Theodore W. Richards states that he has begun his investi- 

 gation of the birth and growth of crystals as studied by the micro- 

 kinetoscope, and has already obtained various excellent photographs 

 illustrating these phenomena, which also give promise of interesting 

 results as to the rate of growth of different crystals. 



Charles R. Cross, Chairman. 



Report of the C. M. Warren Committee. 



10 May, 1899. 



At the last Annual Meeting of the Academy the sum of $600 from the 

 income of the Warren Fund, was granted to Professor C. F. Mabery, 

 of Cleveland, Ohio, in furtherance of his researches on petroleum. 

 Several papers explanatory of Professor Mabery's results have been 

 published during the year; and it is well understood that his work is 

 being prosecuted all the while with ardor and success. 



A research by Professor F. C. Phillips, of Allegheny City, in aid of 

 which a grant of $200 was made in 1896, has been in so far completed 

 that an account of it was published, in November last, in the Proceed- 

 ings of the Academy, under the title " On Fluctuations in the Composi- 

 tion of Natural Gas." 



A grant in the sum of $200 made to Professor H. O. Hofman, of 

 Boston, in 1897, and supplemented in 1898 by an additional grant of 

 130, has also borne good fruit. Professor Hofman's subject was "The 

 Fusibility of Slags." He has explained to me that interesting and 

 important results have been obtained, which he intends to publish in the 

 near future. 



F. H. Storer, Chairman. 



