Plo] AND SYMBOLS. 271 



endowed with very remarkable hygrometric properties. In the 

 dry season, when every particle of moisture is extracted from 

 the soil, it is detached from its growing place, rolled up into a 

 ball, and carried away by the violent equinoctial gales which 

 prevail at the time in these regions, often to very great dis- 

 tances. It remains coiled up in this form for a considerable 

 time ; but if carried to a marsh, or the margin of a stream, or 

 any other moist place, it begins slowly to unfold, and spread 

 itself out flatly on the soil, assumes its former vigour and fresh- 

 ness, takes root, develops its fructification, and casts abroad its 

 seed upon the air. When this new situation is dried up, it 

 resumes its old unsettled habits, and takes advantage of the 

 wind to emigrate to a more favourable locality. It is like an 

 adventurous pilgrim whose very constitution seems to make 

 him long for perpetual changes, and whose temperament is 

 adapted admirably for a roving life. B 



Unexpected Pioneers. 



You write down as absurd, and despise as quixotic, many 

 men whose movements you cannot follow, and whose cause 

 you do not understand. But, remember, many such men have 

 been the pioneers of the race. They have pursued their own 

 course steadily and honestly. The glories of the discoveries to 

 which their pathway would lead the coming generations were 

 too splendid for even their eye of faith to behold, but subse- 

 quent ages have gazed on them with rapture and gratitude. And 

 such men are not the only examples of humble pioneers who have 

 performed services for humanity. Geography is under obliga- 

 tions to yet more lowly friends, for it is a remarkable fact that 

 the North American bison or buffalo has exerted an important 

 influence on geographical discoveries in pathless mountain dis- 

 tricts. These animals advance in herds of many thousands in 

 search of a milder climate during winter in the countries south 

 of the Arkansas river. Their size and cumbrous forms render it 

 difficult for them to cross high mountains on these migratory 

 courses, and a well-trodden buffalo-path is therefore followed 

 wherever it is met with, as it invariably indicates the most 

 convenient passage across the mountains. Thus, as Humboldt 



