LECTURES. 107 



and sub-division of them, each had to go through certain traditional 

 and poetical periods, till it gained that certainty in its outlines which 

 it at present exhibits. 



Every blue summit of a mountain descried by your western settlers 

 and pioneers from a distance, every large or small branch of a new 

 river, every glittering surface of a lake never seen before, was talked 

 of by them around their camp-fires, and gave occasion to all manner 

 of hypotheses and speculations about the end of the lake, about the 

 direction and source of the river, and about wliat those mountains 

 might be, what they might contain, and how they might be connected 

 with the rest. And what those bold pioneers surmised, and what 

 they heard from the Indians in the west, all found an echo in the 

 cabinets of the geographers of the east, and you see it conscientiously 

 transferred to their maps, which are changed and corrected a hundred 

 times, till at length a Champlain, a Boone, or a Clarke fits out his 

 expedition and sets the matter at rest. 



To follow out such laborious undertakings, and to trace the zigzag 

 lines of their progress through the course of whole centuries, may to 

 some appear a very tedious work. I regard it, on the contrary, as a 

 branch of investigation both novel and exciting. It is a department 

 of historical inquiry which is unique in its kind, because it treats of 

 human efforts and achievements which when once brought to a satis- 

 factory termination are incapable of renewal. Asia, in the course of 

 ages, may yet be conquered by more than one Alexander or Grenghis 

 Khan. But a Columbus will never appear again, because he per- 

 formed a work which, from its nature, can never be repeated. The 

 islands, and mountains, and rivers, of our globe are numbered; and 

 the time must arrive when the race of discoverers shall become extinct. 

 But the glory of the Corteses, the Drakes, the Cooks, Avill then shine 

 brighter than ever. These were the men who struck the great blows 

 in carving out the right figure of our globe, and in fundamentally 

 changing the aspect of all human affairs. They wrote their names 

 on the rocks and shores which they discovered, and there they will 

 stand so long as the pillars of Hercules and the limits of the ocean, 

 and of the dry land shall last. Their history, as I have said, is 

 unique, and therefore ought to be written and delivered to posterity 

 with especial care and accurateness. If we, who are comparatively 

 still near to these remarkable events, omit to do this, if we neglect 

 the valuable document^ which are still at our command and allow 

 them to perish, posterity will justly reproach us with having deprived 

 humanity of a part of its most interesting records. 



rV. — USE OF FORMER MAPS FOR COMPLETING AND TESTING THE ACCURACY OF 



THE NEW ONES. 



The field of geographical research through all tlie vast regions of 

 a great continent like America is immense. And although scientific 

 observers are now more numerous than ever, it has been perfectly 

 impossible for them to bring up the observations of every point, har- 

 bor, cape, and inlet, of every source, turn, angle, and mouth of a 

 river to the point of accuracy which science now demands. 



In fact, I believe the number of places of which the position, nature, 



