far-seeing prudence; and the same spirit seems to pervade the laws annexed, which savor of mature deliberation. It is to be regretted that this important collection has met with so little attention from Humboldt. In his Essai Politique, nearly 200 pages are devoted to the description of the mines in New Spain, chiefly of sections, and to statistical material, while the history of mining receives comparatively little attention. The view taken by this scientist refers rather to its condition at the time of his visit, and even the recently established code of laws did not elicit from him any special comments. This leaves another void in the mass of information furnished by him, yet its value is undoubted. Subsequent writers have nearly all followed his steps, and it would be impossible to write the mining history of New Spain without consulting the statistics which form the chief fruit of his researches.
The want of a commentary on the mining ordinances was early recognized by the able Mexican mineralogist, Joaquin Velazquez de Leon, and supplied by him in the Comentarios de las Ordenanzas de Minería, MS., pp. 62. They by no means exhaust the subject, and cover only special points, but they have an additional interest in coming from the pen of a man who took active part in the compilation of the code, and whose ability gave him a right to interpret not only the letter but the spirit thereof. Among other authors who have thrown some light on the mining industry of New Spain are Fonseca and Urrutia, who in their Historia General de Real Hacienda, i. 5-44, 297-387, iii. 6-140, iv. 521-636, v. 43-57, give much information, together with copies of official documents which in many cases are unattainable to foreigners. The value of the work is, however, much impaired by a deficient arrangement and their method of handling the bulky material at their disposal. Of modern writers, Alaman ranks prominent, less on account of the extent of his information, than for the reliable statements which he presents in different parts of his Disertaciones and Historia de Mejico. His ability has been acknowledged by Ward, who, in his Mexico in 1827, several times confesses his indebtedness to Alaman in no stinted terms. Ward admits also to have largely drawn from Humboldt, but his work dwells chiefly on the condition of Mexican mines after the Independence, and belongs therefore more properly to that period. This applies also to Burkart, Aufenthalt und Reisen in Mexico, Stuttgart, 1836, 2 vols, pp. 392, 286, with maps and cuts. This author was at different times manager of the mines of Tlalpujagua and Bolaños, and the ample opportunity thus offered him to make investigations, united with his professional knowledge, has been freely exercised with good result. I shall have occasion to speak of him again as well as of Duport, whose Métaux Précieux, Paris, 1843, pp. xiii. 429, with cuts and maps, corresponds with about the same period.
In addition to these a number of treatises exist, bearing on special subjects, one of the oldest being the Providencias sobre Azogues, 44 folios, a manuscript coetaneous copy on stamped paper of the regulations and orders issued from 1670 till 1673 by Viceroy Mancera, for the distribution of quicksilver to the miners. The influence of that metal on the mining industry of New Spain and the opportunies for raising or lowering its price gave repeatedly occasion for troublesome questions. Instances of these disputes are found in Compendiosa Demostracion, Mexico, 1743, pp. 178, and Seganda Demostra-