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stranger not seasoned to the climate from approaching the beds of those attacked by the vomito. No fact can be cited to render it probable that the immediate contact or breath of the dying person is dangerous to those not seasoned to the climate, who may attend on the patient. On the continent of equinoctial America, the yellow fever is not more contagious than the intermittent fevers of Europe.

Pringle, Lind, and other distinguished physicians, consider our summer and autumnal bilious affections as the first degree of yellow fever. A feeble analogy is also discoverable in the pernicious intermittent fevers which prevail in Italy. In the low regions of Mexico, as well as in Europe, the sudden suppression of perspiration is one of the principal occasional causes of the gastric or bilious fe

vers.

The strangers who frequent Vera Cruz have greatly exaggerated the dirtiness of the inhabitants. For some time the police has taken measures for the preservation of the salubrity of the air; and Vera Cruz is at present not so dirty as many of the towns of the south of Europe; but these precautions must be continued for some years before their good effects will be sensibly felt.

An intimate connexion is observed on the coast of Mexico between the progress of diseases, and the variations of the temperature of the atmosphere. Two seasons only are known at Vera Cruz, that of the tempest of the north (los Nortes) from the

autumnal to the spring equinox, and that of the breezes or south winds (brizas), which blow with considerable regularity between March and September. The month of January is the coldest in the year, because it is furthest from the two periods in which the sun passes through the zenith of Vera Cruz. The vomito generally begins first to rage in that town when the mean temperature of the month reaches 75° Fahr. In December, January, and February, the heat remains below this limit; and accordingly it seldom happens that the yellow fever does not entirely disappear in that season when a very sensible cold is frequently felt. The strong heats begin in the month of March, and the epidemical scourge begins at the same time. Although May is warmer than September and October, it is however in the two last months that the vomito commits the greatest ravages; for in every epidemic it requires a certain time before the germ of the disease is developed in all its energy; and the rains, which last from the month of June to the month of September, have an undoubted influence on the production of the miasmata which are formed in the environs of Vera Cruz.

The beginning and the close of the rainy season are dreaded the most under the tropics, because an excessive humidity arrests, almost as much as a great drought, the progress of putrefaction of the vegetable and animal substances which are accumu

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lated in marshy situations. More than 90 inches of rain-water fall annually at Vera Cruz; and in the month of July 1803 alone, an accurate observer, M. Costanzo, colonel of the corps of engineers, collected more than 25 inches, which is only one-third less than the quantity which falls at London during the whole year.

It is a very remarkable fact, that during the eight years which preceded 1794, there was not a single example of vomito, although the concourse of Europeans and Mexicans from the interior was extremely great.

CHAPTER VII.

Mineral productions-quantity of gold and silver-copper, tin, iron, lead, mercury, coal, salt.

HAVING given a brief general view of the soil, climate and population of the kingdom of Mexico, it remains for us to exhibit a view of the mineral productions which for two centuries and a half have been the object of working the mines of New Spain. The mountains of the New Continent, like the mountains of the Old, contain iron, copper, lead, and a great number of other mineral substances, indispensable to agriculture and the arts. If the labour of man has, in America, been almost exclusively directed to the extraction of gold and silver, it is because the members of a society act from very different considerations to those which ought to influence the whole society. Wherever the soil can produce both indigo and maize, the former prevails over the latter, although the general interest requires a preference to be given to those vegetables which supply nourishment to man, over those which are merely objects of exchange with strangers. In the same manner, the mines of iron

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or lead on the ridge of the Cordilleras, notwithstanding their richness, continue to be neglected, because nearly the whole attention of the colonists is directed to the veins of gold and silver, even when they exhibit on trial but small indications of abundance. Such is the attraction of those precious metals, which, by a general convention, have become the representatives of labour and subsistence.

No doubt the people of Mexico can procure, by means of foreign commerce, all the articles which are supplied to them by their own country; but in the midst of great wealth in gold and silver, want is severely felt whenever the commerce with the mother country, or with other parts of Europe or Asia, has suffered any interruption, or whenever a war throws obstacles in the way of maritime communication. From five to six hundred thousand pounds in piastres are sometimes heaped up in Mexico, while the manufacturers and miners are suffering from the want of steel, iron, and mercury. A few years before my arrival in New Spain, the price of iron rose from about 16s. the 100lbs. to 10%., and steel from 24s. to 547. In those times when there is a total stagnation of foreign commerce, the industry of the Mexicans is awakened for a time, and they then begin to manufacture steel, and to make use of the iron and mercury of the mountains of America. The nation is then alive to its true interest, and feels that wealth consists