24 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



each side of the sun, and to see it after the reappearance 

 of the sun. 



Mr. G. W. Hill made a drawing of the corona at Denver, 

 Col. 



Professor O. Stone and Mr. W. Upton observed the eclipse 

 a few miles east of Denver. Contact and other observations 

 were secured. 



Messrs. L. and G. IT. Trouvelot observed at Creston, and a 

 tine pastel drawing of the corona has been received from 

 them. 



Mr. D. P. Todd, of the Nautical Almanac Office, was sta- 

 tioned at Dallas, Texas, and, in spite of cloudy weather, ob- 

 served contacts. He also secured a number of observations 

 of the duration of totality from volunteer observers stationed 

 near the limits of total eclipse. 



The discovery of Vulcan by Professor Watson is men- 

 tioned elsewhere. 



TRANSIT OF MERCURY, MAY G, 1878. 



The transit of Mercury w r as observed by Professor Hall at 

 Washington. Seventy-two photographs of the planet, when 

 on the disk of the sun, were made at Washington by Mr. Jo- 

 seph A. Rogers with one of the photoheliographs used in pho- 

 tographing the transit of Venus in December, 1874. 



Professor Harkness went to Austin, Texas, to observe this 

 transit. Although the first half of the transit was lost in 

 clouds, he was favored with a clear sky and a steady atmos- 

 phere during the latter half, and succeeded in making twen- 

 ty-five measures of the polar diameter of Mercury, the same 

 number of measures of its equatorial diameter, excellent de- 

 terminations of the instants of third and fourth contact, and 

 a very satisfactory observation of the physical phenomena 

 attend in 2f these contacts. 



The transit was observed by Professor Eastman with the 

 9.6-inch equatorial at the Naval Observatory ; and by As- 

 sistant Astronomers Frisby and Skinner with smaller equa- 

 torials. Professor Eastman observed the second, third, and 

 fourth contacts, made several series of measures of the di- 

 ameter o Mercury, and made a careful study of the physical 

 phenomena at the time of contacts. Assistant Astronomers 

 Frisby and Skinner observed contacts. 



