MINING DISTRICTS. 39] 
their arms, axes, chisels, and other implements. 
With the use of iron they seem to have been un- 
acquainted ; but they contrived to give the requisite 
hardness to their tools by mixing a portion of tin 
with the copper of which they were composed. 
At the period when Humboldt visited New Spain, 
it contained nearly 500 places celebrated for the me- 
tallic treasures in their vicinity, and comprehending 
nearly 3000 mines. These were divided into 37 
districts, under the direction of an equal number of 
councils (Diputaciones de mineria), as follows :— 
I. INTENDANCY OF GUANAXUATO. 
i. Mining: District of Guanaxuato. 
II INTENDANCY OF ZACATECAS. 
2. Zacatecas. 4. Fresnillo. 
3. Sombrerete. 5. Sierra de Pinos. 
III. INTENDANCY OF SAN LUIS POTOSI. 
6. Catorce. 9. Ojocaliente. 
7- Potosi. 10. San Nicolas de Croix. 
8. Charcas. 
IV. INTENDANCY OF MEXICO. 
11. Pachuca. 15. Zacualpan. 
12. El Doctor. 16. Sultepec. 
13. Zuriapan. 17. Temastaltepec. 
14. Tasco. 
Ve. INTENDANCY OF GUADALAXARA. 
18. Bolanos. 20. Hostotipaquillo. 
19. Asientos de Ibarra. 
VI. INTENDANCY OF DURANGO. 
24, Cosiguiriachi. 
25. Batopilas. 
21. Chihuahua. 
22. Parral. 
23. Guarisamey. 
Vil. INTENDANCY OF SONORA. 
26. Alamos. 30. Guadalupe de la Puerta. 
27. Copala. 31. Santissima Trinidad de Pe- 
28. Cosala. na Blanca. 
29. San Francisco Xavier de la | 32. San Francisco Xavier de 
Huerta. ; Alisos. 
