But this is not so much to my present Purpose, as to consider the Air loaded not only with Vapours, but with poisonous _Effluvia_ from the Steams of various Minerals, as well as with the Salts of dead Insects and Animals, which, in the Season of Autumn, may probably occasion so many Agues, and putrid Fevers, as are met with. Now, if you further consider the Air as loaded with any or all of these Vapours and _Effluvia_, and demanding Entrance with the Authority of Fire, its Companion, is it any Wonder, that the Rheumatism, and many other bad Effects, which frequently happen, in unguarded Seasons, to Mankind, may be owing to the Cause here treated of? I remember that a Person, riding in an open Chaise, in an Easterly Wind, receiv’d a Stroke upon one of his _Scapula’s_, with as great Pain, and with the same kind of Sensation, as if he had been stuck with a Dagger. Upon which he instantly said to his Friend in the Chaise, He expected a violent Rheumatism from it. Which accordingly happen’d; for he was not able to quit his Bed for Three Weeks after.—I think this cannot be better accounted for, than to suppose it proceeded from a pointed Body of this kind of Fire, and the _Effluvia_ which accompanied it. If you will be pleased to reflect on the Air in this last described State, you need not expect, I think, to have much said concerning the Blights on Trees. It is true, somewhat may be consider’d with regard to the Insects frequently found on the blighted Leaves: But whether, when by the Blight the Leaves have been curl’d up, the Insects come there as to a proper _Nidus_, or whether they are brought in this Fire, which seems plainly to have burn’d the Leaves, I will not undertake to account for. _I am_, &c. ------------------------------------------------------------------------ APPENDIX. The kind Reception this small Treatise has met with from the Public occasions the Printing this Second Edition of it. It is, I confess, some Satisfaction to me, that my publishing it is not without Part of the Effect I hoped for; having been told by many, who have read it, that it gave them very new and satisfactory Ideas. As to those who have read it, and say nothing of it, either from their Want of Apprehension, or their Fear of being obliged to alter their Sentiments concerning it, or from a worse Cause than either, I absolutely have no Concern about them. There are those, I confess, who merit with me the highest Esteem, who, having read it, object to some Things, as fearing I have not conceiv’d them rightly; but this they have done with the Temper of Gentlemen. These I think deserve to be set right; which I will therefore attempt to do in the following Manner: