TRUE VOLCANOES. 381 



Santa Fe del Nuevo Mexico (lat. 35° 41'), height 7047 

 feet, Ws. 



self. At the time when I was occupied, from March, 1803, to Febru- 

 ary, 1804:, with the astronomical determinations of places in the trop- 

 ical part of Xew Spain, and ventured, from the materials I could dis^ 

 cover and examine, to design a map of that country, of which my re- 

 spected friend Thomas Jefferson, then President of the United States, 

 during my residence in Washington, caused a copy to be made, there 

 existed as yet in the interior of the country, on the road to Santa Fe, 

 no determinations of latitude north of Durango (lat. 24° 25'). Ac- 

 cording to the two manuscript journals of the engineers Eivera, Lafo- 

 ra, and Mascaro, of the years 1724 and 1765, discovered by me in the 

 archives of Mexico, and which contained directions of the compass and 

 computed partial distances, a careful calculation showed for the im- 

 portant station of Santa Fe, according to Don Pedro de Rivera, lat. 

 36° 12', and long. 105 J 52' 30". (See my Atlas Geogr. et Phys. du Mex- 

 ique, tab. 6, am\Essai Pol., t. i., p. 75-82.) I took the precaution, in the 

 analysis of my map, to note this result as a very uncertain one, seeing 

 that in the valuations of the distances, as well as in the directions of 

 the compass, uncorrected for the magnetic variation, and unaided by 

 objects in treeless plains, destitute of human habitations, over an ex- 

 tent of more than 1200 geographical miles, all the errors can not be 

 compensated (t. i., p. 127-131). It happens that the result here given, 

 as compared with the most recent astronomical observations, turns 

 out to be much more erroneous in the latitude than in the longitude — 

 being in the former about thirty-one, and in the latter scarcely twen- 

 tv-three minutes. I was likewise fortunate enough to determine, near- 

 ly correctly, the geographical position of the Lake Timpanogos, now 

 generally called the Great Salt Lake, while the name of Timpanogos 

 is now only applied to the river which falls into the little Utah Lake, a 

 fresh-water lake. In the language of the Utah Indians a river is called 

 og-xcah.be, and by contraction ogo alone ; timpan means rock, so that 

 Timpan-ogo signifies rock-river (Fremont, Explor. Exped., 1815, p. 

 273). Buschmann explains the word timpa as derived from the Mexi- 

 can tetl, stone, while in pa he finds a substantive termination of 

 the native North-Mexican languages; to ogo he attributes the general 

 signification of water : see his work, Die Spuren der Aztehischen Sprache 

 im nordlichen Mexico, s. 351-356 and 351. Compare Expedition to the 

 Valley of the Great Salt Lake of Utah, by Captain Howard Stansbury, 

 1852, p. 300, and Humboldt, Vieics of Nature, p. 206. My map gives 

 to the Montagues de Sel gemme, somewhat to the east of the Laguna de 

 Timpanogos, lat, 40° 7', long. Ill 48' 30"; consequently my first 

 conjecture differs 39 minutes in latitude, and 17 in longitude. The 

 most recent determinations of the position of Santa Fe, the capital of 

 New Mexico, with which I am acquainted, are, 1st, by Lieutenant 

 Emory (1S46), from numerous astronomical observations, lat. 35° 44' 

 6"; and, 2d, by Gregg and Dr. Wislizenus (1848), perhaps in another 

 locality, 35° 41' 6". : The longitude, according to Emory, is 7 h 4' 18", 

 in time from Greenwich, and therefore 106° 5' in the equatorial cir- 

 cle ; according to Wislizenus, 108° 22' from Paris (Xew Mexico and 

 California, by Emory, Document No. 41, p. 36; Wish, p. 29). Most 

 maps err in making tbe latitudes of places in the neighborhood of 

 Santa Fe too far to the north. The height of the city of Santa Fe 



