DURING the late Plague likewise at _London_, a Citizen travelling into the Country, found his Horse of a sudden to tire and fall down, whereupon he opened his Mouth to find out if possible the Cause of so sudden a Change; when the good Man, upon Receipt of the Horse’s Breath upon him, immediately grew sick, and died in two Days Time. BUT these and the like Instances certainly tend to prove no more than that there may be Constitutions and malignant Steams, which, by agitating the Mass of Humours, may excite putrid and irregular Orgasms, wherein the Juices and Animal Fluids, according to the Quantity and Prevalency of the Distemperature, and the Variety of the infused Taint, with the Diversity of Putrefaction, goes into Corruption; but the forementioned Transplantation of the Plague does not happen but where there is a suitable Predisposition of Humours to admit it, as its Cause is not general. MOREOVER, although the Intemperature of the Year, sudden Change of Air, Suppression of usual Evacuation, Diminution of Perspiration, Drunkenness, Venery, and Passions of the Mind, especially Anger and Fear, are justly reckoned amongst the remote Causes of a Pestilence; yet they regard rather the Invasion of it, than its Origin; but of this we shall say more hereafter. As to the above-mentioned Passions, it is almost incredible how some, at the Height of the Infection, would from a very slight Cause kindle into the utmost Rage, and rave at one another like meer Scolds, until Death parted their Contentions. NOR does Fear or Sorrow less prepare the Way for the Infection, by deadning the Fancy and Memory, by Suffocating the Spirits, Suppressing the natural Heat, breaking the Constitution, and Promoting Malignity: We have manifold Instances of this kind in Readiness; but if, as some do, we should be prolix in the Enumeration of Things that want not Proof, the Reader would be quite tired with needless Stories. BUT now it may be convenient to add a few Remarks concerning the Translation of a Pestilence from an hot Country to a cold one; for according to the different Effects of Heat and Cold, the one attenuating and rarefying, the other condensing and constipating, the pestilential Venom is strangely altered, insomuch that in a Thing so obvious, there does not require much to be said: Every Thing of this kind prodigiously spreads in hot Climates, as being more subtile than even the Air it self; tho’ the same in the Northern Countries is more restrained, and confined in Fastnesses it cannot escape from; and from hence the Reason is very obvious why there is so much Difference between the Diseases of different Climates, which would be too tedious for us here to go into.