Report on the Solar Eclipse Expedition to SahdoL 15 



noted by Mr. McA'Fee on a mean time chronometer, carefully com- 

 pared with the clock both before and after. The contacts were 

 observed by throwing a 4-inch image of the sun on white paper from 

 a navy-pattern telescope. [Aperture 2 inches, focal length 28 inches, 

 magnifying power of negative eyepiece 25.] 



Major Burrard observed with a 2-inch telescope, and recorded his 

 times on the chronograph in connection with the sidereal clock. 



This clock was in a grass hut and subjected to a daily variation of 

 50 of temperature, but great care was taken with the star observa- 

 tions, as will be explained in detail in the final report of the Astron- 

 omer Royal. The local mean times of the star observations for clock 

 error (by Major Burrard) were 



January 21 days 18 hrs. 30 mins. 58 sees., and January 22 days 

 7 hrs. 21 mins. 13 sees, and the errors of the clock at these times 

 were, +0 min. 12'83 sees, and +0 min. 14'88 sees, respectively. 



Local Mean Times of the Four Contacts. 



10. Remarks on Formulae jor 'Prediction of Contacts. As was men- 

 tioned in paragraph 5 of the joint report of the Astronomer Royal 

 and Professor Turner, the data for predicting the four contacts were 

 found insufficient. This will be seen by comparison of the last two 

 columns, wherein the times as given by the published formula most 

 nearly suitable for Sahdol are given. On application to the Super- 

 intendent of the 'Nautical Almanac,' he kindly supplied the data for 

 the third column, giving the G.M.T.s of the four contacts, to which 

 the longitude of Sahdol has been applied. 



[The position of Sahdol is 



5 hrs. 25 mins. 26'2 sees. E., Lat. 23 16' 45" K] 

 As his letter contains a suggestion which may be useful to other 

 observers, I reproduce it here. 



