426 THE UNIVERSE. 



Frenchman, while examining one of these trees which he 

 had had cut down, had his face and hands covered with 

 exudation flowing from the broken branches, yet he experi- 

 enced no bad effects from this circumstance. 



But it is very different when the juice of the upas is in- 

 troduced into the organism by means of the smallest punc- 

 ture. A wound of this kind destroys a dog in five or six 

 minutes, as Magendie noticed in his experiments. Eight 

 drops of the juice injected into the veins of a horse kill it 

 directly. 



Other plants, more happily gifted, instead of these deadly 

 poisons, elaborate at the same time medicinal agents and 

 nutritive matters. One of these products furnishes a 

 remedy in sickness ; another increases the luxury of our 

 tables. This is the case with the rhubarbs. Their large 

 roots are quite full of purgative and strengthening prin- 

 ciples, whilst their leaves, saturated with acidulous juice, 

 display strong stocks which serve for food. In England and 

 in the United States an enormous quantity is consumed in 

 the spring for pastry and side-dishes, and at this time of 

 the year trains of vehicles, heavily laden with rhubarb 

 stalks, are seen arriving at the markets. 



For long, a kind of sympathy between certain plants has 

 been observed to exist, as if one loved to be under the 

 shade of the other. Thus on the banks of rivulets the ama- 

 ranth-colored 1 flowers of the purple loosestrife (Lythrum 

 salicaria, Linn.) constantly adorn the vicinity of the wil- 

 low. Other plants, on the contrary, seem to experience 

 an aversion one for the other, and if man inconsiderately 



1 A color inclining to purple. 



