SOLAR ECLIPSE, MAY 6, 1883. 



133 



light, and made an impression not only very positive in its character at the time, hut one not soon 

 forgotten. Diwing totality it was necessary to have a lantern to read a silvered circle. The same 

 circle was read in Colorado in 1878 by Dr. Hastings without any artificial illumination. 



The time of fourth contact was noted on the chronograph at 4'' 8™ 5.8", and was independ- 

 ently noted by Mr. C. H. Rockwell by eye and ear method at 8" CO* by same chronometer. 



The corrections to Negus 1589 on May 6 were as follows : 



The true local sidereal and mean times of contacts, adopting i^ 52"' 48» as the longitude of 

 Caroline Island, were then as follows : 



The experiments to determine the force of gravity at Caroline Island were made from 7 p. m. 

 to 5 a. m., the pendulum being swnng four nights with heavy end down, and two nights with heavy 

 endup; 100 transits of the pendulum-point across the vertical wire of the telescope were noted 

 at the beginning and end of each swing by breaking the electric current and thus registering the 

 transit on the chronogi-aph. " Donkey "transits were also taken during the swing to avoid misiaiiing 

 the whole number of oscillations. The amplitudes of oscillation of the pendulum before and after 

 each set of regular transits, and frequently during the swing, was noted. The barometer was 

 read several times during the night and the temperature was noted, by means of three thermom- 

 eters, continually. The range of temperature, however, was not great. My colleagne in the work 

 has been Ensign S. J. Brown, U. S. Navy. He took part in all observations except those for tiaie. 

 It was thought best to have one pei'son continue these during our whole stay on the island in order 

 that they might not be influenced by a change of personal equation. 



I am, most respectfully, your obedient servant, 



> ERASMUS D. PRESTON, 



Aid U. S. a tfc G. Survey. 



(e) REPORT OF MR. WINSLOW UPTON. 



TJ. S. S. Haetfoed, May 23, 1883. 

 Prof. E. S. Holden: 



Dear Sir : I have the honor to submit herewith a report upon the observations made by 



me in connection with the recent solar eclipse. The work intrusted me was (1) determination of 



