EFFECT OF LIGHT ON PLANTS. 69 



You will soon learn this property of plants ; 

 and observe that those grown in the shade are 

 always both paler and taller than similar kinds 

 grown where the light is admitted freely, and 

 that the colours of plants, particularly the 

 green, depend on light, and light only. This 

 may soon be proved by putting a pot over any 

 growing plant, and you will find that it will 

 lose its green colour ; but that when the light 

 is again admitted, it recovers it. 



Hence the common process of blanching or 

 whitening endive for the table, by tying up the 

 plant with bass, so that the light is shut out 

 from the inner leaves, the putting pots over 

 sea-kale, and covering up celery with earth: 

 all of which, being deprived of light, soon be 

 come white. 



Among the tender annuals, which should 

 now be sown, are coxcombs, tricolours, globe 



