6 ORIGIN OF CULTIVATED PLANTS. 



utility, it is probably because obscure and unknown 

 men have previously spoken of it, and that suc- 

 cessful experiments have been already made. A 

 longer or shorter succession of local and short- 

 lived experiments must have occurred before such 

 a display, which is calculated to impress an already 

 numerous public. It is easy to understand that 

 there must have been determining causes to excite 

 these attempts, to renew them, to make them suc- 

 cessful. 



" The first cause is that such or such a plant, 

 offering some of those advantages which all men 

 seek, must be within reach. The lowest savages 

 know the plants of their country ; but the exam- 

 ple of the Australians and Patagonians shows that 

 if they do not consider them productive and easy 

 to rear, they do not entertain the idea of cultivat- 

 ing them. Other conditions are sufficiently evi- 

 dent : a not too rigorous climate ; in hot countries, 

 the moderate duration of drought ; some degree of 

 security and settlement ; lastly, a pressing neces- 

 sity, due to insufficient resources in fishing, hunt- 

 ing, or in the production of indigenous and nutri- 

 tious plants, such as the chestnut, the date-palm, 

 the banana, or the bread-fruit tree. When men 

 can live without work, it is what they like best. 



