Art. III. — Venus tx Daylight to Eye and to Opera-Glass. 

 — A. Cameron, Yarmouth. 



It seems to be coininonly supposed that Venus can be seen 

 with the naked eye in daylioht on very rare occasions only, and 

 that even then the sight can be enjoyed only by those who have 

 unusually good eyes. It is the chief purpose of this paper to 

 try to show that this is a mistaken notion. 



That such a notion should prevail among- the general public 

 is not so very strange, for the general public nowadays are not 

 much given to looking heavenwards either by night or by day. 

 But it is not confined to the general public! It may be found 

 expressly stated in some astronomical books and periodicals, and, 

 when not expressly stated, remarks are often made by astrono- 

 mical writers which seem to imply that they hold this opinion, 

 and which certainly succeed in conveying that impression to 

 their readers. For instance the following appeared a few^ years 

 ago as an editorial note in an astronomical monthly : — 



" Some friend havino- the initials P. B. S. claims to have seen 

 Venus with the naked eye Jan. 1 and 14 at the hours respectively 

 of half-past one and half-past twelve in the afternoon This may 

 be possible, l»ut it is also certainly true that our friend has unu- 

 sual power of vision." 



Tlie man who wrote that is an astronomer. He is, and he was 

 then, the director of an astronomical observatory^ as well as the 

 editor of an astronomical journal. If the reader of this paper 

 will note the fact that, when P. B. S made his observation, Venus 

 was 3| months out from her nearest conjunction, he will by and 

 by be able to see wdiat an absurd mistake the editor made. It is 

 only fair to add that he afterwards admitted that he had written 

 "inadvertently." 



This paper is a sequel to one called " The Visibility of Venus to the Naked Ey»," published in 

 last year's Transactions (Ser. -ind, V'ol I, Art. III). When the earlier paper is referred to here it 

 is usually spoken of as " the Visibility paper." 



The latitude of the writer's station is 44' N., longitude 6(5° W., time used 60° VV. 



The numbers given for Venus's brilliancy at different times are percentages of the mean greatest 

 brilliancy. 



