The morbid changes that are met with in the bodies of those who die from plague are very similar to what we find in typhus, yellow fever, and in the carcases of animals that have died in consequence of a putrid matter injected into their veins. The vessels of the brain and its mem branes are gorged with a dark coloured blood; the lungs and liver present traces of inflammation or of gangrene; patches of inflammation and ulceration are met with in the stomach and intestines; the heart is of a pale red colour, easily torn, and full of black blood, which, according ,to M. Magendie, never coagulates. These changes however are not always found, and the same absence of appreciable organic lesion is sometimes observed in typhus and other diseases which prove rapidly fatal. No age, sex, or profession appears to enjoy an immunity from plague, nor does one attack secure the individual from future infec tion; but it has been observed that old persons, women, and children suffer less frequently and severely from its attacks than robust adults. Some persons also, who exercise particular trades, as knackers, tanners, water-carriers, bakers, and oilmen, seem to share this advantage; while smiths and cooks were noticed, during the campaign in Egypt, to be more particularly liable to it. One law appears to be universal in all plagues, namely, that the poor are the first and chief sufferers. In Grand Cairo, Constantinople, and Aleppo, it is in the low, crowded, and filthy parts of those cities, occupied by the poorest people, that the plague commits its greatest ravages. The celebrated plague of Mar seille, in the year 1720, first appeared in a part of the city noted for the sordid filth, crowded state, and wretchedness of the poor inhabi tants. This was likewise true of Loudon, where, from the same cir cumstance, it obtained the appellation of the Pooes Plague. Like many other diseases, plague is observed in two forms : first, as an indigenous and local disease, peculiar to the inhabitants of certain countries, and from which they are never entirely free ; and secondly, as a raging and fatal epidemic, not confined to its original seat, although exhibiting itself there in its most intense forms. It is the epidemic variety of this fatal malady that has engrossed so much attention from the earliest times down to the present; and we shall therefore briefly pass in review some of the principal circumstances which attend its origin, progress, and termination.
It has been observed that nearly all plagues have been preceded by certain natural signs, and by a greater mortality from malignant diseases generally than at other times. Among these precursory
signals, great and sudden atmospheric vicissitudes have been noted. Livy (v. 13) attributes the origin of a pestilence to this cause. " The year was remarkable," ho observes, " for a cold and snowy winter, so that the roads were impassable and the Tiber completely frozen. This deplorable winter, whether it was from the unseasonable state of the air, which suddenly changed to an opposite state, or from some other cause, was succeeded by intense heat, pestilential and destructive to all kinds of animals." But in the great plague of Athens, of which Thucydides has given so minute a description 48, &c.), he observes that the year of the plague was particularly free from all other diseases ; and he mentions nothing unusual as having occurred in pre ceding years. The city however was then greatly over-crowded with inhabitants, a great part of the population having taken refuge within the walls of Athens (ii. 16), in consequence of the war. [Pimicr.Es, BIOG. Div.] Russell informs us that the winter of 1756-7, which pre ceded the petechial fever of 1758 at Aleppo, and the plague of 1759 60-1-2 in different parts of Syria, was excessively severe. Olive-trees which had withstood the weather for fifty years were killed. In the following summer a dearth ensued from the failure of the crops, and so severe a famine, that parents devoured their own children, and the poor from the mountains offered their wives for sale iu the markets to buy food. The connection between famine and pestilence has been noticed in all ages of the world. An enormous iucrease of insects has frequently been observed to precede a pestilence. We are informed by Short, that in 1612 Constantinople was infested with crowds of grasshoppers of great size that devoured every green thing, and the next year (1613) the plague carried off 200,000 inhabitants of that city. In 1612, swarms of locusts laid waste the vegetable kingdom in Provence; and in 1613 the plague appeared in different parts of France. Locusts and pestilence are frequently mentioned together in the sacred writings; and we find that the plagues of Egypt exhibited a series of phenomena, rising in progression from corruption of the rivers and fountains, swarms of insects, murrain among cattle, thunder and thick darkness, and a tribe of inferior diseases, to that fatal pesti lence which swept away tho first-born of the Egyptians. In fine, dearth or unwholesome provisions, pestilence auaoug cattle, great