Chap. IX. PRELIMINARY REMARKS. 325 



otlier deleterious plants. Sir Andrew Smith informs me that 

 in South Africa a large number of fruits and succulent leaves, 

 and especially roots, are used in times of scarcity. The 

 natives, indeed, know the properties of a long catalogue of 

 plants, some having "been found during famines to be eatable, 

 others injurious to health, or even destructive to life. He 

 met a party of Baquanas who, having been expelled by the 

 conquering Zulus, had lived for years on any roots or leaves 

 which afforded some little nutriment and distended their 

 stomachs, so as to relieve the pangs of hunger. They looked 

 like walking skeletons, and suffered fearfully from con- 

 stipation. Sir Andrew Smith also informs me that on such 

 occasions the natives observe as a guide for themselves, what 

 the wild animals, especially baboons and monkeys, eat. 



From innumerable experiments made through dire ne- 

 cessity by the savages of every land, with the results handed 

 down by tradition, the nutritious, stimulating, and medicinal 

 properties of the most unpromising plants were probably 

 first discovered. It appears, for instance, at first an in- 

 explicable fact that untutored man, in three distant quarters 

 of the world, should have discovered, amongst a host of 

 native plants, that the leaves of the tea-plant and niattee, 

 and the berries of the coffee, all included a stimulating and 

 nutritious essence, now known to be chemically the same. 

 \Ve can also see that savages suffering from severe con- 

 stipation would naturally observe whether any of the roois 

 which they devoured acted as aperients. We probably owe 

 our knowledge of the uses of almost all plants to man 

 having originally existed in a barbarous state, and having 

 been often compelled by severe want to try as food almost 

 everything which he could chew and swallow. 



From what we know of the habits of savages in many 

 quarters of the world, there is no reason to suppose that our 

 cereal plants originally existed in their present state so 

 valuable to man. Let us look to one continent alone, namely, 

 Africa : Earth 6 states that the slaves over a large part of the 



8 ' Travels in Central Africa,' Eng. ii. pp. 29, 265, 270. Livingstone'* 

 iranslat. vol. i. pp. 529 and .i90 ; vol. ' Travels,' p. 551. 



