conceivable with what fury it attacks the coasts of Britain; and it is very well known, that it commonly blows above half the year (which was alfo obferved by Julius Cæfar) and that very violently, especially in the autumn; whence our Michaelmas ftorms and rain. Philos. Trans. No. 352. In these instances, the frequent rains are the confequences of winds, paffing over a large tract of water; and this may lead us to the reason, why the winds come so much from the south-weft in Cornwall, that we have known them blow from that quarter the four last months of the year, almoft without intermiflion, attended by violent floods of rain, which took all the time before mentioned to arrive at the deep bottoms; about which feafon, at Christmas, or very foon after, the wind fhifts to the oppofite point of the compafs, and generally brings along with it the little froft and cold this country is fubject to; mean while, the Waters are determined to the bottoms of our deep Mines, merely by the time they have had to fink down through the earth. The impatient obferver wonders at this flow descent of the Waters; and when the wind fhifts to the eastward, he very injudiciously attributes the effect to a wrong cause. We confefs, the above feems to us a very natural and plain explication of the affair; but as we have not that deference for our own opinion, as always to prefer it to others, we are ready to acknowledge ourselves open to conviction, if a better reason shall be advanced at any future time. And as a hint to our readers, we defire they will confider, how far the denfity and confequential preffure of the atmosphere may contribute to this appearance more than a hundred fathoms underground. It is true, the Mines are continually fraught with a kind of warm vapour, which may be feen to arife from every fhaft, when the air is cool, clear, and dense; and it may be supposed, that, as it afcends through the natural and artificial outlets of its womb, it is more or lefs condenfed by the external air, in proportion to the rarity or denfity thereof. But if this folution appears plaufible to fome, we defire to be informed, why this should not be more apparent, when the wind blows from the north and why this vapour, if not of the dry kind, fhould not be condenfed in the fhafts and gunnies (hollows) of a Lode, after the manner of rain, as other vapours are, and, therefore, be as diftinguishable in its production, as in its exiftence? F ; From From the foregoing proofs, that rain Water penetrates to the depths of the earth, we may be fatisfied, that the opinion of De la Hire, Calcott, and others, who fay, rain Water does not fink two feet below the furface, is altogether erroneous; for if it does not enter into the bowels of the earth, what else should occafion fo vaft an increase thereof, at, or foon after, its difcharge from the clouds? So apparent is this fact, that if the great increase and collection of Water from the heavens, before mentioned, be obstructed in its circulation, and collected into large bodies, by the peculiar matter or form of its recipient, it may, and has many times appeared to be the cause of local earthquakes; which, we apprehend, may proceed from the Water of higher grounds, that gets underneath a flimy viscous earth or clay, until the force of the confined Water moves it upward, and carries the earth along with it in its paffage and irruption; of which we may produce an inftance, at Kappanihane in Ireland, A. D. 1697; another of Pilling Mofs, in 1745; and a more recent one, in the late accounts we have had, of Solway Mofs in North-Britain: As if on earth, Winds under ground, or Waters, forcing way, MILTON. As for those earthquakes, which are more general, tremendous, and destructive; it is probable they are caused by the combination of different falts, juices, fulphur, or fome other inflammable matter, that rarifies and agitates the air, in the deep caverns of the earth; whereby a convulfion is caufed, which fometimes breaks out in flames at the furface; and fometimes fhocks and gives the earth a tremulous motion, without any vifible fire, perhaps for want of fufficient matter to ignite. For, if you add twenty pounds of fulphur to twenty of iron filings, and mix these with water, fo as to form a pafte; in fix or seven hours after they have been buried a foot and half under ground, the earth will begin to tremble, crack, and smoke, and fire and flame will burst through; fo that there wants only a fufficient quantity of this matter, to produce a true Etna. If it was fuppofed to burst out under the fea, it might occafion a new ifland and we believe Delos, Rhodes, and fome other iflands were produced by the fame, or fuch like fubmarine volcano. (Pliny) An island in the Archipelago on the coast of Natolia, Natolia, in 1707; another among the Azores, in 1720; and four islands in a lake, in the Manilla, A. D. 1750; are productions in the prefent century, from the fame cause. Worthington advances, "That the fole cause of the formation "of mountains, was an universal earthquake.” Dr. The immenfe congregation of Iron, Sulphur, and other combuftible materials, with which our mining district is fo replete, would naturally incline us to believe our fituation more obnoxious to fubterranean throes, than any other part of GreatBritain. But, by the mercy of our GRACIOUS PRESERVER, We have hitherto felt nothing peculiarly to alarm us, on account of our fituation. Many are of opinion, that our numerous shafts, adits, and other apertures, are the principal outlets, through which the mineral effluvia of our Lodes exhale and escape, without prejudice to the lives and safety of the inhabitants. Another prodigious, general, and effective cause of earthquakes, is an electrick æther in the atmosphere, according to the opinion of the learned Dr. Stukely; and from this force, extended to a confiderable diftance, through various substances, of different textures and denfities, we may attribute the destruction of no less than thirteen great and noble cities in Asia Minor, in one minute's time, in the year of our Lord 17. Another earthquake in Peru, anno 1586, extended 900 miles; and we may add that memorable earthquake in our own days, upon the 1ft of November 1755, which destroyed Lisbon, and was felt over almost half the habitable globe. We may apply either of thefe caufes, under fuch certain fituations and circumftances, as may incline our judgment to preponderate. But may not all of them operate for the fame effect? We think they may and who can fay, it is not fo? For with Job we may fay, "Lo, these are parts of God's ways; "but how little a portion is heard of him? And the thunder "of his power who can understand?" Omnipotence being the directing caufe, all things are equally accomplished by the natural instruments of his power: and when we hear the thunder of his voice, and fee the mightiness of his power, the dreadful, though partial convulfions, of an angry, yet merciful God; ought we not to meditate upon the hitherto harmless, though alarming tokens we have had of his indignation, tempered with love? Of all the natural warnings of his difpleasure, those of earthquakes are most terrifick; coming like a thief in the night, when when the fons of men know not of it! We may flee from the peftilence, the famine, and the fword; we may avoid the dangers of the fea, and provide against fire; we may secure our habitations from lightening, tempefts, inundations; we may, by the affiftance of fkilful applications, and the wisdom of the phyfician, baffle the attacks of difeafe, to the prolongation of our lives. But no flight, no prudence, no philofophy, no delay, can obviate this defolation: for, it is as the prefence of God! How thankful then, ought we to be! how humbly should we walk before him, who hath hitherto fpared us, in the midst of his judgments! O Lord God; for the abundance of our fins, thou art greatly to be feared; and yet we fee that in great mercy, thou prefideft over all thy works! Though it is remarkable, that the Water of a Mine, at or near the fea cliffs, is very eafy and fmall, efpecially when the Mine is funk under low Water mark, or works under the fea; yet it is abfolutely certain, that it is lefs in proportion to the ground difcovered under the level of the fea, than above. How this should be, is one of the most puzzling questions that can be put to the Miners, who, to a man, ingenuously confefs their ignorance of the true cause of it. The gentleman and the philofopher are equally at a lofs to account for this fact, except Mr. Bennallack, who fays, "That in the places where he has "had opportunities of judging properly, the only apparent "caufe is, that the ftrata being more compact, and confe quently more free from those fundry kinds of fiffures, which "the Miners in general call Cafes, there are not the fame conveyances for the Waters of the furrounding country to flow "into the Mine." In Huel-Towan in the parish of St. Agnes, where they are not many fathoms under low Water mark, the facts of the Water being lefs, and the ground more compact, are inconteftible; nor, in that place, does any other matter appear conducive to it. We believe this may be one natural cause in fome particular places, but it cannot be always fo; and we likewife believe, that there may be other contributing matters, which may be different, in different fituations. We will have reourse to the moft fimple and plain enquiry into the form and texture of the earth, in the folution of this phenomenon, diftinct from our knowledge of the preffure and gravity of fluids: but before we proceed, we beg leave to illuftrate our fubject, by a very remarkable hiftory of a case in point. The The Mine of Huel-Cock in the parish of St. Juft, is wrought eighty fathoms in length, under the fea, beyond low Water mark; and the fea, in fome places, is but three fathoms over the back of the workings; infomuch, that the Tinners underneath hear the break, flux, ebb, and reflux of every wave, which, upon the beach overhead, may be faid to have had the run of the Atlantick-ocean for many hundred leagues; and, confequently, are amazingly powerful and boisterous. They alfo hear the rumbling noife of every nodule and fragment of rock, which are continually rolling upon the fubmarine ftratum; which, altogether, make a kind of thundering roar, that will furprise and fearfully engage the attention of the curious stranger. Add to this, that feveral parts of the Lode, which were richer than others, have been very indifcreetly hulked and worked within four feet of the fea; whereby, in violent ftormy weather, the noise overhead has been fo tremendous, that the workmen have many times deferted their labour under the greatest fear, left the fea might break in upon them. This proximity of the fea over the workmen, without their being incommoded by the falt Water, is more wonderful, than the account which Dr. Stukley gives, of his defcending into a coal pit at Whitehaven one hundred and fifty fathoms deep, till he came under the very bed of the ocean, where fhips were failing over his head; being at that time, deeper under-ground by the perpendicular, than any part of the ocean between England and Ireland. In his cafe, there is a vaft thickness of ftrata between the Mine and the fea; but, at Huel-Cock, they have only a cruft between, at moft; and though, in one place, they have barely four feet of ftratum to preferve them from the raging fea, yet they have rarely more than a little dribble of falt water, which they occafionally ftop with oakum or clay, inserted in the crannies through which it iffues. In a Lead Mine in Perran Zabuloe, formerly wrought under the fea, they were fometimes fenfible of a capillary stream of falt Water, which they likewife prevented by the fame means, whenever they perceived it. Now, a very large proportion of our Mine Water is temporary; and, as I have faid before, is denominated Top Water, which in great part finks into the Mine immediately where it falls, by the peculiar loose texture of ftrata where Mines are, which must be cavernous and fiffured, to conftitute and form thofe receptacles of mineral particles called Lodes, and their lateral branches: confequently, the ready accefs of this Top Water, must be very fenfibly perceived by the Miners; and |