CHRONOMETRIC CONNECTIONS. 35 



in Table XV., as well as the differences of longitude inferred by each 

 chronometer. 



79. From Table XV. we have the following results for the difference of 

 longitude between Honolulu (Apua) and Kailua observatories : 



m s 



By the first run, 1874, Dec. 5 to Dec. 10 (7 chronometers) 7. 24-38 



By the second run, 1874, Dec - H to Dec. 18 (22 chronometers) . . 7. 24-65 

 By the third run, 1875, Jan. 2 to Jan. 6 (22 chronometers) 7. 24- 89 



Mean, Kailua transit east of Honolulu (Apua) 7. 24*64 



And for the difference of longitude between Honolulu and "Waimea we 

 have : 



m 8 



By the first run, 1874, Dec. 19 to Dec. 21 (22 chronometers) 7. i3'6g 



By the second run, 1874, Dec. 22 to Dec. 24 (22 chronometers) . . 7. i3'3i 

 By the third run, 1876, Jan. 9 to Jan. 12 (22 chronometers) 7. 13-44 



Mean, Waimea Observatory west of Honolulu (Apua) 7. 13-48 



80. In the year 1872 Professor Forbes and I made some com- 

 parisons to discover our relative personal equation, by observing many 

 stars about the same time in the same instrument, with the following 

 results : 



8 



May 21, clock slow, T F = +0-04 weight 2" 



May 22, = + o-i3 2 



ivr VMean +o s -o5. 



May 27, = +0-08 2 f 



' June 10, = o-i3 



At Kailua, on December 15, 1874, a rather unsatisfactory comparison was 

 made which gave T F = +0 8< 04. These results tend to show that there 

 is no great difference between Professor Forbes and myself ; consequently no 

 correction for personal equation has been applied to the difference of longi- 

 tude between Honolulu and Kailua. 



No data exist for comparing Mr. Johnson's mode of observing with mine ; 

 the difference of longitude, therefore, between "Waimea and Honolulu is 

 affected by this relative personal equation to an unknown extent. Mr. Johnson 

 used a half-seconds chronometer when observing transits ; at Honolulu, of 

 course, the clock was employed. 



F 



