222 HYPSOMETRIC ADDENDA. 



French feet. Eng. feet. Observer. 



Mexico - %-M ' 7008 799 Ht 



Tula :,P ,, 6318 6733 Ht. 



San Juan del Rio *-'^ 6090 6490 Ht. 



Queretaro ''.V- 597 6363 Ht ' 



Celaya **"* '"'^\ - 5646 6017 Ht. 



Salamanca - :; * / 5406 5761 Ht. 



Guanaxuato - < - - 6414 6836 Ht. 



Silao - n> : ? #k 5546 5910 Br. 



Villa de Leon - 5755 6133 Br. 



Lagos - 5983 6376 Br. 



Aguas Calientes - - " - - 5875 6261 Br. 



San Louis Potosi W~- 5714 6090 Br. 



Zacatecas - ' / ||i ' ; 7544 8040 Br. 



Fresnillo 6797 7244 Br. 



Durango ' - - 6426 6848 (Oteiza) 



Parras - '%&-" ' 4678 4985 Ws. 



Saltillo - 4917 5240 Ws. 







BBolsondeMapirm - '. - 



Chihuahua - i; *^ I -*+*> k*<** ' 4352 46 38 Ws. 



Cosiquiriachi . ? -. 5886 6273 Ws. 



Passo del Norte, on the Rio Grande del Norte 3557 3812 Ws. 



Santa Fe del Nuevo Mexico" ' -' 6612 7047 Ws. 



The letters Ws., Br., and Ht., are placed to distinguish the baro- 

 metric measurements of Dr. Wislizenus, Oberbergrath Burkart, and 

 my own. Wislizenus has appended to his valuable memoir three 

 vertical sections of the surface of the ground : one from Santa Fe to 

 Chihuahua by Passo del Norte; one from Chihuahua to Reynosa by 

 Parras ; and one from Fort Independence (a little to the east of the 

 confluence of the Missouri and the Kanzas River) to Santa Fe. The 

 calculation is founded on daily corresponding observations of the 

 barometer, made by Engelmann, at St. Louis, and by Lilly at New 

 Orleans. If we consider that the difference of latitude between 

 Santa Fe" and Mexico is 16, and that thus (apart from deviations 

 from a straight line) the distance in the north and south direction is 

 above 960 geographical miles, we are led to inquire whether there be 

 in any other part of the whole globe a similar conformation of the 

 earth, equal in extent and elevation (between 5000 and 7000 French, 



