VENUS IN DAYLIGHT— CAMERON. 3o3 



importance of knowing exactly where to look for her is a matter 

 of course. There is another important matter, already incident- 

 ally mentioned, which may not seem to be so much a matter of 

 course. Its importance has often been impressed on me when 

 searching with the naked eye for any bright planet or star in 

 daylight or in strong twilight. I have of course been careful to 

 know beforehand just what point in the sky I should look to- 

 wards, and, to make it easier to direct my eye to the very spot, 

 I have so arranged matters that the spot should be very precisely 

 located with respect to sou:ie terrestrial object, — a chimney, or a 

 steeple, or a flag-pole, or something of that sort. The nearer to 

 this object the sky-spot is, the more surely you can j)oint your 

 eye straight towards it. But then the eye is very apt to adjust 

 itself for seeing an object just at or a little beyond the chimney 

 or flag-staff which you are using as a point of reference. I have 

 often noticed this in myself and still oftener in others whom I 

 have been trying to get to see some celestial object that was just 

 visible in a daylight or twilight sky. Under these circumstances 

 it is very essential that the observer should make the effort to 

 focus his eye for a very far-off olvject. As he does so, and as 

 success begins to reward his effort, he will tind himself experien- 

 cing a curious and pleasing sensation. The star, after being first 

 dimly glimpsed, will seem to be advancing towards him from an 

 infinitely remote distance. It will appear at first as a mere flut- 

 tering speck, but will grow more and more distinct and more 

 and more steady as it seems to float nearer, until, when the exact 

 eye-adjustment has been made, it takes up a fixed position as a 

 point of light just wdiere the observer has been steadily gazing 

 all the time. " Swims into his ken " exactly expresses what 

 seems to happen, and I have often wondered if Keats had been 

 picking out stars in a sunset sky just before writing his lines on 

 Chapman's Homer. It is only when the object is at about the 

 extreme limit of visibility that I have noticed this apparent 

 swimming motion. At other times, if there is some delaj^ in 

 getting the object into the eye, the observer is most apt, when he 

 does get it, to be overwhelmed with surprise that he should have 

 missed it before. 



