178 Total Eclipse of August 7, 18G9. 



General J. W. Keifer, Springfield, Ohio, C. B. Bost- 

 wick, Mattoon, 111. Naked eye, observations on corona, &c 



Trot'. F. II. Smith, Mattoon, 111. Observation of bud 

 thermometer. 



President Thomas Hill, Cambridge, Mass. Naked eye 

 observations on corona, shadow and other phenomena. 



Prof. G. W. Hough. Dudley Observatory — Equatorial 

 comet-seeker, 4 in. objective, 3 ft. 6 in. focus, power 44. 



The station at Mattoon was near the west side of the 

 school building, twenty feet north of the South monument, 

 erected by the United States Coast Survey. The position 

 was a good one, as there was an uninterrupted view to the 

 south, west and east. 



In the south-west room was mounted the sidereal clock 

 and chronograph. The clock was a compensated mercury 

 pendulum, made in two sections for facility of transporta- 

 tion; the mercury being held in an air tight iron cylinder. 

 This clock was made expressly for the eclipse expedition 

 b} 7 Charles Fasoldt, of Albany, to whom we are also under 

 obligations for a mean time pocket chronometer, beating 

 three times per second. 



Before packing, the clock was set up in the Observatory, 

 and rated on sidereal time, and the necessary connections 

 attached for recording minutes and seconds on the chro- 

 nograph. Its running for nearly a week, as compared 

 with the standard clock, showed a steady and reliable rate. 

 On arriving at Mattoon, Aug. 2, it was immediately 

 mounted on a solid brick wall, and started on Mattoon si- 

 dereal time, as deduced from the watch by applying 

 difference of longitude, <vc. In the afternoon of the same 

 day. by comparison with the watch, it was found going too 

 slow. A small brass weight equivalent to five seconds per 



day on the rate, was placed on the pendulum. After 

 which time it was not disturbed. By subsequent compa- 

 risons with Dudley Observatory time, obtained by means 



