NOTES. CXXX111 



introduced by my friend the learned geographer Contre-Amiral de Fleurieu, the 

 author of the Introduction historique au Voyage de Marchand, has the fault of 

 giving to a part the name of the whole, and tends, therefore, to cause confusion. 

 ( M4 ) p. 391. On the axis of the greatest heights or culminating points, 

 and of the volcanoes in the tropical zone of Mexico, see Kosinos, Bd. iv. S. 312 

 and 343 (in the present volume, p. 268 and 299). Compare also Essai pol. sur 

 la Nouv. Esp. t. i. p. 257268, t, ii. p. 173; and Ansichten der Natur, Bd. i. 

 S. 344350. 



( 535 ) p. 392. By Juan de Onate, 1594. Memoir of a Tour to Northern 

 Mexico in 1846 and 1847, by Dr. Wislizenus. On the influence which the 

 peculiar form of the ground (the great magnitude of the table-land) may be ex- 

 pected to exert on internal traffic and on the intercourse of the tropical zone with 

 the north, whenever social order, civil liberty, and industry shall be enjoyed, 

 compare Essai pol. t. iv. p. 38; and Dana, p. 612. 



( 536 ) p. 392. In this tabular view of elevations between Mexico and Santa 

 Fe', as in the similar, but less complete, one given in rny Ansichten der Natur, 

 Bd. i. S. 349, the initials B., W., and H. signify the names of the observers: 

 W. being Dr. Wislizenus, author of a very instructive and scientific work, 

 Memoir of a Tour to Northern Mexico connected with Colonel Doniphan's Ex- 

 pedition in 1846 and 1847 (Washington, 1848); B., Oberbergrath Burkart ; 

 and H., myself. At the time when I was engaged in astronomical determina- 

 tions of latitude and longitude in the tropical parts of New Spain (from March 

 1803 to February 1804), and when, from all the materials that I could discover 

 and discuss, I ventured to prepare a general map of the entire country, of which 

 map my honoured friend, Thomas Jefferson, then President of the United States, 

 had a copy made which has since been often much misemployed, there were 

 as yet no determinations of latitude in the interior of the country, on the 

 route to Santa Fe', north of Durango (24 25' N.). According to two manu- 

 script accounts of travels found by me in the archives of Mexico, of the 

 engineers Rivera, Lafora, and Mascaro, in 1724 and 1765, containing compass 

 bearings and estimated partial distances, careful calculation gave for the im- 

 portant station of Santa Fe 36 12' N., and 105 51' W. (from Don Pedro 

 de Rivera). (See my Atlas ge'ogr. et phys. du Mexique, Tab. VI. : and Essai 

 pol. t. i. p. 75, 82.) In the analysis of my map, I have carefully stated 

 this result to be a very uncertain one, inasmuch as, in estimations of dis- 

 tance and compass bearings, without correction for the magnetic declination, 

 and with the want of objects in treeless plains without human habitations, on 

 an extent of 1200 geogr. miles, it cannot be safely assumed that all errors 

 compensate each other (t. i. p. 127131). It happens accidentally that 



