EFFECT OF LIGHT. 451 



during the season of growth. This may be reme- 

 died by proper drainage ; secondlj/, from gathering 

 the fruit before saccharine fermentation has com- 

 menced ; and, thirdlj/, from absorption of too much 

 oxygen. This may generally be remedied by judi- 

 cious pruning, which admits the light. A ray of 

 light is composed of several colors, each of which 

 has independent and peculiar qualities, and pro- 

 duces distinct chemical results. By the union of 

 two or more rays, compound colors may be pro- 

 duced, which combine the effects of the rays com- 

 posing them. Every vegetable cell has a nucleus, 

 which, exposed to the light, takes some color, gen- 

 erally green. Upon the skin of fruits these colors, 

 changing from green to yellow, and then to brilliant 

 red, seem to mark or produce chemical changes 

 which result in the ripening of the fruit. When 

 this change of color in the skin of the fruit does 

 not take place, the fruit seldom ripens ; or, if it 

 does become mellow, the flavor will be very inferior, 

 showing that the usual chemical changes have not 

 been thoroughly performed. The amount of color 

 necessary to a fruit to bring it to perfection varies, 

 of course, in different varieties. The Rhode Island 

 Greening apple, in its most highly colored state, is 

 yet very pale when compared with a Baldwin only 

 moderately so. Those fruits which require little col- 

 or are generally peculiarly sensitive in regard to the 

 least. Such is the Vicar of Winkfield pear, which 



