OP ARTS AND SCIENCES. 375 



Seven hundred and twenty-ninth Meeting. 



March 10, 1880. — Stated Meeting. 



The President in the chair. 



On the motion of Professor Cooke, it was 



Voted, That, when the Academy adjourn, it adjourn to the 

 second Wednesday in April. 



The following papers were presented : — 



" On Stellar Spectra." By Edward C. Pickering. 



"On the Atomic Weight of Antimony." By Josiah P. 

 Cooke, Jr. 



Mr. Michelson described a plan for measuring the velocity 

 of the solar system through space. Remarks upon this com- 

 munication were made by Professors E. C. Pickering and 

 W. A. Rogers. 



Seven hundred and thirtieth Meeting. 



April 14, 1880. — Adjoubned Stated Meeting. 



The President in the chair. 



The Corresponding Secretary read a letter from Professor 

 J. Willard Gibbs, acknowledging his election as Associate 

 Fellow of the Academy. 



Professor Lovering presented the following vote of the 

 Rumford Committee : — 



" Voted, That the Academy be recommended to confer the 

 Rumford Medal on Professor Josiah Willard Gibbs for re- 

 searches in thermodynamics." 



Mr. Theodore Lyman spoke of the progress of the contri- 

 butions to the centennial fund, 'and stated that the Presi- 

 dent's address would be delivered in the Old South Church, 

 and that after the address a reception would be held at the 

 hall of the Academy. 



The following papers were presented : — 



" On the Present State of the Question of Standards of 

 Length." By W. A. Rogers. 



