It is hardly necessary for me to observe, that no disease followed the destruction and putrefaction of these locusts. The colony of South Africa still continues free from plague and cholera, and many other diseases afflicting the most favoured of European lands; consumption, scrofula, and fever are all but unknown. I am not aware that the inhabitants are in any way remarkable for their sanitary arrangements, whilst of the Hottentots it may with truth be said, that they are at once the healthiest and dirtiest people in the world. Thus, after the lapse of many centuries, the great questions debated in the time of Justinian--may we not rather say in the days of Thucydides?--surge up again whenever a new plague appears on the earth. The professors of “the conjectural art,” anxious to vindicate their claim to activity, and to share in the laudations bestowed on the superior intelligence of the present day, offer at present a highly consolatory view, not only as to the origin of these diseases, but as to their speedy suppression. They argue that, but for the neglect of hygienic measures, such influences or poisons would either not arise, or would pass on their course, leaving the nations unscathed. In the meantime, it is prudent to recall to the recollection of those who arrive rashly at conclusions such as these--who theorize on narrow local ground--who are sanguine enough to look forward to the speedy extinction of all zymotic diseases, that pestilential and destructive epidemics are not confined to man; that, under the form of murrains, they destroy the beasts of the field. In the murrain of 1747, it is stated on authority that 30,000 cattle died in Cheshire in the course of half a year. The marsh districts suffered most; and it has even been conjectured that such epizootic diseases usually originate amidst swamps and malarious districts; but of this we have no proofs. Even the harvests to which man looks for sustenance are not spared--nor the vine; the life-destroying principle, attacking these lower forms of life, cannot well be traced to the neglect of hygienic measures on the part of man, or of the animals or plants themselves; and yet in the midst of these bogs and marshes which undeniably give origin to some forms of fever, the buffalo, the ox, the camel, the elephant, and the wild of all species, live and thrive. Thus the question of the origin of disease is complicated _ab origine_; the origin of typhus--that scourge and pest of the nations inhabiting the temperate regions, more especially of Western Europe, and of the British Isles in particular--is absolutely unknown. To affect to trace it to a foul drain, an uncleansed sewer, an untrapped cesspool, a laystall, a collection of neglected rubbish, is clearly against the evidence and the daily experience of thousands; but all are agreed that in certain fenny and marshy countries fevers prevail--intermittent in temperate,