VENUS IN DAYLIGHT — CAMERON. 345 



Of course astronomers have other and more important matters 

 ^o attend to than such a subject as this : but, when they do 

 write about it, it were well that what they write should not be 

 untrue or misleading. 



It is just the kind of subject that a star-gazing hobbyist is apt 

 to get interested in. My own interest in it grew out of the fact 

 that I found my observations inconsistent with the general drift 

 of what I had read about it — which general drift tended to con- 

 firm the common but erroneous opinion already mentioned. In 

 fact, so far as I can remember, everything I ever read about it, 

 with one exception, tended that way. The one exception, — and 

 it would have been a very startling announcement to me had not 

 Venus herself prepared me for it, — was a paragraph in L'Astron- 

 omie for June, 1892. It contains one of the ' conclusions ' which 

 M. Trouvelot of the Observatory of Meudon draws from many 

 years' observation of Venus. He says : 



" Par un ciel pur Venus est visible a I'oeil nu, en plein jour^ 

 sur tour les points de son orbite quand sa distance angulaire 

 au Soleil n'est pas inferieure a 10*^, quand elle est vers ses con- 

 jonctions inferieures, et, a 5'^, quand elle est vers ses conjonctions 

 ^uperieures." 



I did not see this until two months after I had written the 

 article on the Visibility of Venus, which was published in last 

 year's transactions. That article was intended at first to include 

 the present subject, but I am glad now that it did not. For 

 since it was written, and since M. Trouvelot's paper was pub- 

 lished, both an inferior and a superior conjunction have occurred, 

 and I can now set down observations made at these times and 

 compare them with M. Trouvelot's covclu,\ion. 



It might not be amiss, in passing, to compare his conclusion 

 with the statement in the closing sentence of the Visibility arti- 

 cle. There it is said — " On ever};' clear day this year so far " 

 (the year was 1892, and the time of writing was April) " Venus 

 could have been seen, even at noon, by any eye of average 

 quality tha knew where to look for her; and the same sight 

 may be had by the same kind of eye on every clear day from 

 now till the end of the year, excepting onl}^ for a fortnight or 



