[Sidenote: * _See_ Num. 10. Phil. Transactions p. 166-171; _at the time of the printing whereof, this Relation of Mr._ Boyle _was not yet come to hand._] As to the _Earth-quake_, your curiosity about it makes me sorry, that, though I think, I was the first, that gave notice of it to several of the _Virtuosi_ at _Oxford_; yet the Account, that I can send you about it, is not so much of the _Thing_ it self, {180} as of the _Changes of the Air_, that accompanied it. To inform you of which, I must relate to you, that riding one Evening somewhat late betwixt _Oxford_ & a Lodging, I have at a place, 4 miles distant from it, the weather having been for a pretty while Frosty, I found the Wind so very cold, that it reduced me to put on some defensives against it, which I never since, nor, if I forget not, all the foregoing part of the Winter was obliged to make use off. My unwillingness to stay long in so troublesome a Cold, which continued very piercing, till I had got half way home-ward, did put me upon galloping at no very lasy rate; and yet, before I could get to my Lodgings, I found the Wind turned, and felt the Rain falling; which, considering the shortness of the time, and that this Accident was preceded by a setled Frost, was surprising to me, and induced me to mention it at my return, as one of the greatest and suddainest Alterations of Air, I have ever observ'd: And what changes I found, have been taken notice of in the _Gravity_ of the _Atmosphere_ at the same time by that Accurate Observer * Dr. _Wallis_, who then suspected nothing of what follow'd; as I suppose, he has ere this told you himself. Soon after, by my guess about an hour, there was a manifest _Trembling_ in the House where I was (which stands high in comparison of _Oxford_.) But it was not there so great, but that I, who chanced to have my thoughts busied enough on other matters, than the weather, should not have taken notice of it as an _Earth-quake_, but have imputed it to some other cause, if one, that you know, whose hand is employed in this Paper, and begins to be a diligent observer of Natural things, had not advertis'd me of it; as being taken notice of by him and the rest of the people of the House. And soon after there hapned a brisk Storm: whereupon I sent to make inquiry at a place call'd _Brill_, which standing upon a much higher ground, I supposed might be more obnoxious to the effects of the _Earth-quake_ (of which, had I had any suspition of it, my having formerly been in one neer the _Lacus Lemanus_, would have made me the more observant:) But the person I sent to, being {181} disabled by sickness to come over to me (which he promis'd to do, as soon as he could) writ me only a _Ticket_, whose substance was, That the _Earth-quake_ was there much more considerable, than where I lodged, and that at a Gentlemans house, whom he names (the most noted Person, it seems, of the neighbourhood) the House trembled very much, so as to make