THE VEGETABLE KINGDOM. 



397 



freshest foliage. But if, on the contrary, the main mass 

 of the root be encircled with suitable soil, whilst the fine 



220. Mandragora with its Rootlets in Water, Living — Atropa 3Iandragora, 



extremities are scattered in the dry sand, the subject of 

 the experiment fades, languishes, and dies. 



An instinctive irresistible power guides the root to its 

 goal. Nothing checks it; to attain this it cleaves the rock, 

 traverses the water, and hangs and twists in a thousand ways. 



A New England Acacia, which had become weakly and 

 languishing after having exhausted the sterile soil in which 

 it was planted, at last driven to quench its thirst, threw 

 out one of its roots across a hollow of sixty-six feet, in 

 order to plunge it into a neighbouring well, and spread 

 out its fibres in the midst of the water. From this time, 

 according to Malherbe, to whom we owe the history, the 

 tree reared its sinking boughs and blighted leafage, after 

 which it grew with marvellous rapidity.' 



1 Dr. Davy brought forward a case in which a horse-chestnut grew on a flat 

 stone, the roots passing for 7 feet up a wall, then turning over the top of the 

 "wall, and down again for 7 feet to the earth. — Tr. 



