The black cattle of the Sierra do not endure the climate of the coast: immediately that they descend from their native mountains, to use the vulgar expression, they become touched; that is, they become stupified, and die with amazing rapidity. On examining the entrails of cattle thus cut off, the liver, which has a broiled appearance, is observed to be indurated. I conceive that these animals are affected by transition of climate in the same manner as the human species; for, as soon as bullocks from the high and cold regions of the Andes arrive on the warm coast, the circulation of their blood is unusually accelerated and directed to the surface; but, as the skin which covers them is too thick and unyielding to allow of proper transpiration, the consequence is that there arises an ardent fever which destroys them. In beeves this fever is more violent and burning than it is in the paco or alco, because the skin of the latter, being of thinner texture than that of oxen, offers less resistance to the outlet of the humours; so that in the animals of finer skin there comes out a salutary eruption, which saves them; while in black cattle nothing of this sort occurs, and therefore they perish with incredible celerity.[52]
The butchers have not yet found out a remedy for this disorder. They only know from experience that the mortality among the cattle is greater in summer than in winter: a fact confirmatory of our conjectures as to the nature of the distemper: and therefore it is during the winter, or misty season on the coast, that cattle are driven down from the mountains to supply the Lima market.
Should we compare the dogs reared in this city with those allowed equal freedom in the cities of Upper Peru, it will be found that the former are most indolent and indifferent to everything, so that any one, though an entire stranger, may step over them without the least molestation; but the latter surly curs it is necessary to approach with caution, because they attack all persons with whom they are not well acquainted and on friendly terms.
These animals are subject, especially in spring, to catarrhal epidemics which are peculiar to themselves; and they are also liable to influenzas by which mankind are affected, it being among them that the fatal epidemic commenced in the Trojan army.
Neither in Peru, nor in the neighbouring sections of South America, were dogs ever known to be attacked by hydrophobia prior to 1803; but about this time the malady broke out, during the heat of summer, in the valleys of the northern coast, from whence it extended southward along the maritime plains; having arrived at the city of Arequipa in the spring of 1807, while in Lima it was observed between the summer and autumn of the same year.
Having collected all the necessary data for disclosing the origin of this disorder, and consulted in writing the physicians and well-informed persons who had witnessed its symptoms, I have clearly learned,—1st. That this disease arose spontaneously from the increased atmospherical temperature of the years 1803 and 1804. It commenced on the northern coast, commonly called Costa Abajo, where the air was so heated that Reaumur’s thermometer indicated the temperature of 30° in some of the valleys: the calms were extreme, without the lightest breeze that could ripple the surface of the ocean; animals rushed into lakes and pools of still water to relieve themselves from the sensation of excessive heat; so that the season described by Horace was fully realized:
Jam Procyon furit,
Et stella vesani Leonis:
... caretque
Ripa taciturna ventis.