Dr. _Mead_, who thinks it necessary to premise somewhat in general concerning the Propagation of the Plague, might, to the three Causes he has laid down, of a bad Air, diseased Persons, and Goods transported from Abroad, have added the Aliment or Diet, because affording Matter to the Juices it does not less contribute to the Generation of Diseases: And it may be observed, that in the Year before the pestilential Sickness, there was a great Mortality amongst the Cattel from a very wet Autumn, and their Carcasses being sold amongst the ordinary People at a very mean Price, a great many putred Humours might proceed from thence; and this, in the Opinion of many, was the Source of our late Calamities, when it was observed this fatal Destroyer raged with greater Triumph over the common People: And the feeding on unripened and unsound Fruits are frequently charged with a Share in Mischiefs of this Kind. _Galen_[7] is very positive in this Matter, and in one Place accuses[8] his great Master to _Hippocrates_ with neglecting the Consequence of too mean a Diet: From this 'tis generally observed, that a Dearth or Famine is the Harbinger to a following Plague. And we have an Account from our Merchants trading to _Surat_, _Bencoli_, and some other Parts of the _East-Indies_, that the Natives are never free from that Distemper, which is imputed to their low and pitiful Fare. The _Europeans_, especially the _English_, escaping by their better Diet, by feeding on good Flesh, and drinking of strong generous Wine, which secures them from the Power of that Malignancy. Their Hypotheses as widely differ in the very Substance or Nature of the Pestilence; and Dr. [9]_Hodges_, [10]_Mead_, and [11]_Quincey_, have asserted, that it proceeds from a Corruption of the Volatile Salts, or the Nitrous Spirit in the Air. Dr. [12]_Bradley_, from the Number of poisonous Animals, Insects, or Maggots which at that Time are swimming or driving in the circumambient Air; and being sucked into our Bodies along with our Breath, are sufficiently capable of causing those direful Depredations on Mankind called the Plague. Both these Opinions are supported by the Authorities of Learned Men. And if _Hodges_, _&c._ have the Suffrages of the greatest of the ancient Physicians, with those of _Wolfius_, _Agricola_, _Forestus_, _Fernelius_, _Belini_, _Carolus de la Font_, _&c._ _Bradley_ may challenge to him the famed _Kirchir_, _Malhigius_, _Leeuwenhooch_, _Morgagni_, _Redi_, and _Mangetus_. It is almost endless as well as altogether needless, to cite all the Authorities for the different Opinions, that might be collected from the most remote Antiquity down to the present Age. And although it is yet to be contested, and might be held an occult Quality with those learned Gentlemen, we shall find, each Doctor passes his favourite Opinion upon the World with as much Infallibility as a Demonstration in _Euclid_.