289 



OBSERVATIONS OF THE EGRESS OF VENUS, 1874, DECEMBER 8, 

 AT MOKATTAM, NEAR CAIRO. 



REPORT OF CAPTAIN C. ORDE BROWNE. 



For practice in observation of the actual phenomena, as far as possible, a 

 working model had been brought out, similar to that previously used at 

 Greenwich (Plate V.). Mr. Hunter was in this respect at a disadvantage, 

 having his time much taken up by his preparations at Suez. He found time, 

 however, to practice a little on the model at Mokattam. 



At Mokattam the work of preparation consisted in the trial and the 

 improvement of the working of the observing instruments, in the model 

 practice, and rehearsals of the operations at sunrise. 



The De la Rue Equatorial had taken the place of the Altazimuth, and with 

 its clock and movable dome was in admirable working order. 



Convenient observing seats and other arrangements, in accordance with the 

 directions issued by the Astronomer Royal, had been made. 



MAHMOUD BEY, the Director of the Egyptian Government Observatory at 

 ABBASSEYAH, had repeatedly visited the Mokattam Station, and had watched 

 the phenomena of contact on the model ; and it may here be noticed that 

 Dr. AUWERS and M. DOLLEN, who visited the station at Mokattam, had 

 expressed their concurrence as to the phase of formation of the black drop, if 

 any were seen, which ought specially to be observed at Egress, namely, the 

 instant when the connexion which was forming assumed the same blackness 

 as the body of the planet. 



During the first week in December there was much mist in the plain of 

 Cairo, and on the three mornings preceding the day of the transit the Sun 

 had been wholly invisible at Mokattam, except for about 20 minutes on one 

 occasion. 



About sunset on December 8, by order of the KHEDIVE, a considerable body 

 of cavalry trotted up to the camp and picketed for the night. Infantry and 

 police subsequently arrived, and were posted on the following morning so as 

 to form a cordon round the station to prevent the approach of strangers. 

 During the night I obtained transits of stars through openings in the 

 clouds. 



