150 Crimson Star. 



matic, I was surprised to find it distinctly pale yellow ; and, 

 from the intensity of light with the larger aperture, it did not 

 lose this colour even when brought face to face with 7 in the 

 large field of the comet eye-piece. Its real tint, then, had 

 been suppressed, in the finder, by the superior strength of the 

 yellow rays of its overbearing neighbour, and even forced into 

 a slightly complementary hue. As I have no reason to think 

 this a peculiarity of my own vision, it may serve to show how 

 much caution must be used in deciding upon the tints of the 

 lesser components of pairs, when the larger is of any decided 

 colour ; and this, it seems, will be especially the case in pro- 

 portion to the apparent smallness, as well as, of course, the 

 closeness, of the pair. For not only is the effect of contrast 

 increased by the juxta-position of the images on the retina, 

 but by difference of brightness, enabling the stronger to force 

 a complementary tint upon the weaker light ; and difference 

 of brightness, again, becomes more sensible in proportion to 

 the diminution of the total quantity of light ; for it has been 

 remarked by H., that " to any one accustomed to the use 

 of large telescopes, the fact must be familiar, that the apparent 

 inequality of two stars seen at once in the same field of view 

 diminishes as the light of the telescope is greater." Hence it 

 may be conjectured that, could we be gradually transported 

 nearer and nearer to some remote and obscure pairs, where an 

 orange is associated with a much feebler blue companion, we 

 should find the difference of colour decrease as the brightness 

 was augmented, till at length the blue might become white, 

 or even yellow, when liberated from the preponderance of the 

 superior tint. And hence follows the importance of examining 

 suspected star-colours with different apertures, and relying 

 chiefly upon comparisons of observations with the same in- 

 strument. 



The effect of contrast in colour is pleasingly illustrated by 

 the following anecdote of the late great French painter, Dela- 

 croix, related some time ago by Alexander Dumas, at one of 

 his " conferences" : — *' f Delacroix used to tell, that it was while 

 painting Marino Faliero that he had discovered his theory 

 of colours. He required for his decapitated Doge and his 

 senators cloaks of cloth of gold, and he had employed to no 

 purpose the most brilliant yellows — his cloaks continued of a 

 tarnished appearance. He determined then to go to the 

 Louvre, to study the works of Rubens, to attempt to steal from 

 this second Titan the fire of heaven. He accordingly charged 

 Jenny, his housekeeper, his manager, his nurse — in a word, 

 his maitre Jacques — to go and bring }iim a cab. Jenny came 

 at the end of a quarter of an hour to tell him that the cab was 

 at the door. Delacroix descended his staircase rapidly, and, 



