606 PROCEEDINGS 01 Mil. AMERICAN ACADEMY 



with success, and h as low a> wave length 900 tenth-meters, 



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

 with the Bpectra of gases, and Btated thai he could not go below wave 

 length l 600 for metals." 



Professor I I'.. Hale states that the Bpectro-heliograph, in the 



d of which he has been aided by a grant from the Bnmford 

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

 introduced whereby photographs of prominences or facnlae can be taken 

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

 eruptive prominences the comparison of photographs made in this way 

 may prove to be Lnstructivi ." 



Professor Theodore W. Richards states that he lias 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. 



Chable8 R. Cross, Chairman. 



Report of the C. M. Warren Committee. 



10 May, 1899. 



At the last Annual Meeting of the Academy the sum of SC00 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 <:rant of $200 was made in 18'.H'>, 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 (las." 



A grant in the sum of $200 made to Professor II. O. Ilofnian. of 

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

 . lias 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. II. Storek, Chairman, 



