103 [ 237 ] 



of making such a station of use, T think that no observer can neglect it 

 without regret. For, in territories htile known, and which civilized man 

 is visiting for the first time, a latitude deduced from even a single series 

 for a point, whence but a few years ago you would on the morrow have 

 continued your route without having been able to do anything by the 

 methods then known and employed, acquires a value ; and if, in this 

 chance of some favorable instants, your chronometer allows you to reckon 

 a difference of longitude, you have added a geographical position, which, 

 however imperfect it may be, according to circumstances, is yet always 

 better than nothing. Thus, since by employing the method of which I 

 have been speaking, an observer wants only one hour to determine his 

 geographical position, v/e may easily conceive the importance of the ser- 

 vice he can render to geography by a little activity and a judicious distri- 

 bution of his time. In geographical explorations loe can neglect nolhing, 

 or we are pursued and punished by bitter regrets, which arise directly we 

 have left the station behind, to tell us that we have failed to draw from the 

 means in our power all that was offered to us. These regrets revive with 

 even more intensity at the period of constructing the maps. 



1 have made considerable use in this method of the North star ; and when 

 1 recall the time and expense it has saved, I feel a lively gratitude, both to 

 that astronomer who first knew how to make it simple and exact, and thus 

 recommended it to the practice of geographers, and to those scientific men 

 who have made its application still more easy and short, by introducing it 

 annually in the form of tables, in the - Ephemerides of the Heavens." 

 Hare I not reason to entertain such a sentiment in reflecting that, of 590" 

 or 600 geographical positions, more or less completed, which 1 have had 

 occasion to observe during seven years of journeying under American skies, 

 there are not fifteen, the determination of which has not been efficaciously 

 contributed t© by the North star ? 



The methods which science places at the disposal of the geographer, in 

 relation to the problem of the latitude, are truly remarkable, and form a 

 system as complete as could be devised. There remains not an instant of 

 the night or day in which this problem cannot be now practically solved, 

 provided only some region of the heavens be presented disencumbered of 

 clouds. 



For my part, 1 have not disdained to make use even of the method prac- 

 tised at sea for finding the latitude hij two altitudes of the sun. This 

 method gives a good result when one is able to combine the times of the 

 observations, so as to satisfy the conditions required by the theory ; but, 

 even under less favorable circumstances, a suflicient accuracy can still be 

 obtained for geographical purposes. 1 have employed it in those cases 

 where, coming unexpectedly upon geographical points of some interest, 1 

 could fit the halt for the observation with that required ; for instance — for 

 the morning's meal, or to allow a rest to the men and horses of the expedi- 

 tion during the heat of the afternoon. I have also applied it whenever, 

 having held up early in the day at a ])lace which 1 intended to make an 

 astronomical station at night, the indications of the barometer caused rne 

 to fear the occurrence of a sky unfavorable to my object; while I wished 

 to avoid, nevertheless, the loss of a station to which I could not spare more 

 than that one night. The observations of this sort are numerous in my 

 journal ; but the number to which I have been obliged to have recourse is 

 very limited, owing to the good fortune of having been enabled to make 



