Negroes employed as Messengers.
One description of men whom I have omitted to mention before, are negroes employed as messengers by the various chiefs in the Capitania of Minas Geraes. The men selected for this employment are the most trusty and able-bodied that can be found. Their letters are locked up in a leathern bag, which they buckle round them, and never take off until they deliver its contents. They carry a gun and ammunition with them to defend themselves, as well as to provide themselves with food. Wherever they halt, they are sure of a kind and friendly reception, for nothing can exceed the cordiality with which the negroes welcome each other. These men are trusted on very important missions, and are despatched to every part of the Capitania. On urgent occasions, some of them have performed journeys with astonishing celerity. I was most credibly informed, that one of them had been known to travel seven hundred miles on a mountainous road in sixteen days, though that distance usually occupies twenty or twenty-one days. The men are generally tall, and of spare habit; they are accustomed to light food and long abstinence.
Diseases peculiar to the Country.
Of diseases I did not hear of any that were contagious, except Psora, which sometimes prevails among the lower orders, who rarely use any remedy against it, nor will they hear of sulphur, as they believe it to be fatal. Colds, attended with fever, are the most general complaints; but consumptions are rarely heard of. Among the miners, I saw no symptoms of elephantiasis, though that disease is so common in many other parts of Brazil, particularly on the sea-coast. The sciatica which afflicts travellers after long journeys on mules, is attributed by the people of the country to the bodily heat of those animals, which is much greater than that of horses, and communicates to the loins of the rider, occasioning almost constant excruciating pain, which frequently becomes chronic, and sometimes incurable. Being, on my return from the diamond district, much tormented with this complaint, I was naturally led to make inquiries on the subject, and was informed, that a person in the house where I then resided, had returned from a long journey in the same predicament, and was about to undergo the mode of cure commonly practised in the country. I was desirous of inquiring the nature of it, and begged to be introduced to him. On conversing with him, I found that his symptoms were similar to mine; he complained of great pain in the os sacrum, and down the left thigh to the knee, which afflicted him most when in bed, where he could not bear to lie in any posture for half an hour together, but was obliged to rise and wait until the warmth was abated, when he lay down again. Thus he could get no sleep night or day. On asking if he had tried any external application as a stimulus, he replied, that neither that nor any other remedy was of the smallest avail, except the one peculiar to the country. The operation was as follows:—The patient lay down on a bench with his back upwards, and a youth, twelve or fourteen years of age, knelt upon his loins, and continued to trample them (as it were) with his knees for about the space of half an hour, until the muscles were entirely bruised. In a few hours afterwards, the part became highly discolored. If one operation had not the desired effect, another, and even a third, would be had recourse to. It must be confessed, that this remedy, in removing one evil, occasions another; but the advantage is, that the latter is of short duration, whereas the former endures sometimes for life, and gives continual affliction. In some cases the remedy has been applied with success, but in others it has entirely failed.
On the Use of Mercury in the Mining Department.
The Government of Brazil would find it highly to their interest to promote the use of mercury in the gold district. The process of amalgamation is so simple, that there would be no difficulty in introducing it generally among miners; and it would save much time and labor in the last operation of washing, or what is called purifying.
Perhaps it may not be improper, in this place, to describe the method pursued in working the silver mines on the coast of Chili, which may be estimated to produce about a million of dollars annually. Some of these mines are full fifty yards deep; and we are told of one nearly as many fathoms. It is probable that they are sunk upon veins of ore; and they are so ill secured, that they frequently fill, and bury those within them. The metal is generally a sulphuret of silver with antimony, lead, and blende: it is brought up on the shoulders of wretched Indians, who descend and ascend by insecure posts with notches cut in them. They are total strangers to the operations of boring and blasting, and use only miserable hammers and wedges. The vein stuff with the metal is, in some places, reduced by means of a large stone, ill-constructed, rolling on its edge; in others, it is pounded by hand, and, when sufficiently fine, it is washed by several operations in a slovenly manner, until the metallic part alone remains, which is not unlike lead ore dust. This is formed into small heaps, perhaps about 100lb, to each of which are added about 20 or 25lb of muriate of soda[86]. This is triturated and worked both by hands and feet for three or four days. When the salt is judged to be sufficiently incorporated with the metal, mercury is used in the proportion of from five to ten per cent. and is triturated until it loses its globular form; to prove which, a small bit is rubbed upon a horn, or upon the thumb-nail, and if any globules appear, however minute, the trituration is continued until they totally disappear[87]. To this mixture the workmen frequently add filth, rags torn into small bits, &c. place crosses upon the heaps, and use many ridiculous ceremonies dictated by folly and a belief in necromancy. At length the mercury unites with the silver, and forms with it a paste-like mass separating itself from the remainder, which is thrown away. This mass is put into goat-skins, and, by twisting and squeezing, a great part of the mercury passes through, leaving a portion of nearly pure silver, which is afterwards melted. The remainder is sublimed by heat, and is condensed with more or less loss, according to the mode applied, and the skill of the operator. Some little gold is procured from some of the mines on this coast, by a similar process.
In this part of Chili, the state of society is wretched; gambling is a general vice, and assassinations are scarcely regarded as criminal. The greatest depredations are committed with impunity, nor do the crosses placed on the heaps protect them; so that, when a mine proves good, the hopes of the proprietor are often frustrated through the poverty and envy of his neighbours.