154 ON THE VISIBILITY OF VENUS — CAjNIEKON. 



conjunction, when the elonoation was 9 , the pliase ,j|;| and the 

 brilliancy 24. 



Here we are already well within the 20° and 78-day limit, 

 even with niy 48-day and 12 observation, to say nothing" of M. 

 Bruguiere's still better one. As to mine, it was easy enouoh to 

 make, any one might have ma<le it if he had happened to be 

 looking that way at that time. It was the result of a mere ran- 

 dom search, for I had not prepared myself by any previous ol)- 

 servations of sun or stars to know the exact sp(jt in my sky 

 where Venus would be at the time. I felt sure that the 43 days 

 and the 12° could be cut down considerably, but I had to wait a 

 year and a half before there was another chance to try. 



The next superior conjunction occurred in 1890 on February 

 18 at 7 a.m. There is, of course, an opportunity before as well 

 as after each conjunction to try how close to conjunction one can 

 push his o))servations, and, if other things were e(]ual, the before 

 one would be the better of the two ; for the observer would have 

 each day's observation to lielp him in making that of next day. 

 But other things are not ecpial. It is not that there is any 

 difference in the astronomical or other conditions of the thing 

 observed, the difference arises from the personal habits of the 

 observer. Observations of Venus before superior conjunction 

 have to be made in the morning before sunrise ; after superior 

 conjunction, in the evening after sunset ; and under the social 

 conditions of modern life the latter can be made much more con- 

 veniently and comfortably than the former. 8ome time or other 

 — perhaps before next superior conjunction in tlie spring of 1898 

 — I may make up my mind (and my body) to try what can be 

 done by morning observations, but I have nothing of that sort 

 as yet that is worth recording in the present connection. An<l 

 M. Brupuiere seems to be in nuich the same condition. The best 

 observation made before superior conjunction that I find in his 

 list is that of Deceudier 15, 1889, 65 days before the conjunction 

 of February 18, 1890. 



Three weeks after this conjunction, on March 10, I made my 

 first attempt to catch Venus in the evening, but did not succeed. 

 The next live days were cloudy. But the next (March 10) was 



