ON the other hand, it does not appear, that the _Air_, however corrupted, is usually capable of carrying Infection to a very great distance; but that commonly the _Plague_ is spread from Town to Town by infected Persons and Goods: for there are numberless Instances, where the _Plague_ has caused a great Mortality in Towns, while other Towns and Villages, very near them, have been entirely free. And hence it is, that the _Plague_ sometimes spreads from Place to Place very irregularly. _Thuanus_[59] speaks of a _Plague_ in _Italy_, which one Year was at _Trent_ and _Verona_, the next got into _Venice_ and _Padua_, leaving _Vicenza_, an intermediate Place, untouched, though the next Year that also felt the same Stroke: a certain Proof that the _Plague_ was not carried by the _Air_ from _Verona_ to _Padua_ and _Venice_; for the infected _Air_ must have tainted all in its Passage. We have had lately in _France_ one Instance of the same Nature, when the _Plague_ was carried at once out of _Provence_ several Leagues into the _Gevaudan_. Usually indeed the _Plague_, especially when more violent than ordinary, spreads from infected Places into those which border upon them: which probably is sometimes effected by some little Communication infected Towns are obliged to hold with the Country about them for the sake of Necessaries, the Subtlety of the Venom now and then eluding the greatest Precautions; and at other times by such as withdraw themselves from infected Places into the Neighbourhood. I OWN it cannot be demonstrated, that when the _Plague_ makes great Ravage in any Town, the Number of Sick shall never be great enough to load the _Air_ with infectious _Effluvia_, emitted from them in such Plenty, that they may be conveyed by the Winds into a neighbouring Town or Village without being dispersed so much as to hinder their producing any ill Effects; especially since it is not unusual for the _Air_ to be so far charged with these noxious _Atoms_, as to leave no Place within the infected Town secure: insomuch that when the Distemper is at its Highth, all shall be indifferently infected, as well those who keep from the Sick, as those who are near them; though at the beginning of a _Plague_ to avoid all Communication with the Diseased, is an effectual Defence. However, I do not think this is often the Case: just as the _Smoak_, with which the _Air_ of the City of _London_ is constantly impregnated, especially in _Winter_, is not carried many Miles distant; though the Quantity of it is vastly greater than the Quantity of infectious _Effluvia_, that the most mortal _Plague_ could generate.