Miscellaneous Discourses, Addendum
Ʋpon a Review of the Precedent Diſcourſe, ſome Things thought fit to be Added and Amended.
Pag. 51. Lin. 29. Add,
WHich is made one great Reaſon that ſuch great Numbers (even whole Woods) of ſubterraneous Trees are frequently met with and dug up at vaſt Depths in the Spaniſh and Dutch Netherlands, as well as in many places of this Iſland of Great Britan.
Page 70.
Thoſe Words, (nay this latter [the Mediterranean] receives alſo abundance of Water from the great Ocean; running in at the Streights of Gibraltar, and therefore by ſubterraneous Paſſages muſt needs diſcharge their Waters into the Abyſs of Waters under the Earth, and by its intervention into the Ocean again) were written without due Conſideration, in compliance with the common Opinion, before I had ſeen Mr. Halley's *Philoſophic. Tranſact. Numb. 89.Eſtimate of the Quantity of Vapour raiſed out of the Sea by the warmth of the Sun, &c. which upon ſecond Thoughts I find reaſon to revoke. For that the Mediterranean Sea doth not communicate with the Ocean by any ſubterraneous Paſſages, nor thereby impart any Water to it, or receive any from it, may be demonſtrated, from that the Superficies of it is lower than the Superficies of the Ocean, as appears from the Waters running in at the Streights of Gibraltar; for if there were any ſuch Communications, the Water keeping its Level, the Mediterranean, being the loweſt, muſt by thoſe Paſſages receive Waters from the Ocean; and not the Ocean, which is (as we have proved) the higheſt, from the Mediterranean. Hence it neceſſarily follows, that the Mediterranean ſpends more in Vapour than it receives from the Rivers; which is Mr. Halley's Concluſion; tho in ſome of his Premiſes or Hypotheſes he is, I think, miſtaken, as 1. In that he enumerates the Tyber amongſt his nine great Rivers, each of which may yield ten times as much Water as the Thames; whereas I queſtion whether that yields once ſo much; and whereas he paſſes by all the reſt of the Rivers as ſmaller than it; there are two that I have ſeen in Italy it ſelf, whereof the one, viz. the Arnus, on which Florence and Piſa ſtand, ſeemed to me not inferiour in bigneſs to the Tiber; and the other, viz. the Atheſis on which Verona ſtands, I could not gueſs to be leſs than twice as big. 2. In that he thinks himſelf too liberal in allowing theſe nine Rivers to carry down each of them ten times ſo much Water as the Thames doth. Whereas one of thoſe nine, and that none of the biggeſt neither, viz. the River Po, if Ricciolus his Hypotheſes and Calculations be good, affords more Water in an hour, than Mr. Halley ſuppoſes the Thames to do in a day; the hourly Effuſions of the Po being rated at eighteen millions of Cubical Paces by Ricciolus; whereas the daily ones of the Thames are computed to be no more than twenty five millions three hundred forty four thouſand Cubical Yards of Water by Mr. Halley: but a Geometrical Pace contains five Feet, i.e. 1⅔ of a Yard. Now if the Po pours ſo much Water hourly into the Sea, what then muſt the Danow and the Nile do? each of which cannot (I gueſs) be leſs than treble of the Po. Tanau, Boryſthenes and Rhodanus may equal, if not exceed it. Howbeit I cannot approve Ricciolus his Hypotheſes, judging them to be too exceſſive, but do believe that as to the whole Mr. Halley comes nearer the truth▪ Sure enough it is, that in the Mediterranean, the Receipts from the Rivers fall ſhort of the Expence in Vapour: tho in part of it, that is the Euxine, the Receipts exceed, as appears from that there is a conſtant Current ſets outward from thence through the Thracian Boſphorus, and Helleſpont.
But tho the Mediterranean doth indeed evaporate more than it receives from the Rivers, yet I believe, the Caſe is not the ſame with the Caſpian Sea; the Superficies whereof ſeems to me not to bear any greater proportion to the Waters of the Rivers that run into it, than that of the Euxine doth to it; which we have obſerved not to ſpend the whole Receipt in Vapour.
You'll ſay, Why then do not great Floods raiſe the Seas? I anſwer, As to the Caſpian, if it communicates with the Ocean, whether the Rivers bring down more or leſs, its all one; if more, then the Water keeping its Level, the Caſpian raiſeth the Ocean; if leſs, then the Ocean communicates to the Caſpian, and raiſes that. But as to the Mediterranean, we may ſay, that when it receives more on the one ſide, it receives leſs on the other, the Floods and Ebbs of the Nilus and the other Rivers counterbalancing one another; Beſides by reaſon of the Snows lying upon the Mountains all Winter, the greateſt Floods of thoſe great Rivers in Europe do not happen when the Mediterranean evaporates leaſt in the Winter-time; but in the Spring.
You'll demand further, if the Mediterrarean evaporates ſo much what becomes of all this Vapour? I anſwer, it is caſt off upon the Mountains, and on their ſides and tops is condenſed into Water; and ſo returned again by the Rivers unto the Sea.
If you proceed to ask what becomes of the Surpluſage of the Water, which the Mediterranean receives from the Ocean, and ſpends in vapour; I anſwer, It ſeems to me, that it muſt be caſt further off over the tops of the Mountains, and ſupply in part Rain to theſe Northern Countries: for we know that the South-Wind brings Rain, with us and all Europe over.
As to the great Ocean, I do not believe that it evaporates ſo much as the Mediterranean; both 1. Becauſe the whole Mediterranean, excepting the Euxine, lies in a hot Climate, and a great part of it as it were in a Valley, Ridges of high Mountains, Atlas on one ſide, and the Alps and Apennine, &c. on the other running along it. And 2. Becauſe the Surface of the whole Ocean bears a greater proportion to the Waters it receives from the Rivers of at leaſt this Continent, than that of the Mediterranean doth to its. And therefore I think alſo that Mr. Halley exceeds in his Eſtimate of the Heat of the Superficies of the Sea Water. I cannot perſuade my ſelf, that were it all commixt, I mean the hotter part with the cooler all the Surface over to ſuch a thickneſs, it would equal the heat of our Air in the hotteſt time of Summer. But I leave that to further Trial and Enquiry.
Here give me leave to ſuggeſt, that we are not to think, that all the Vapours that ſupply our Rains and Dews proceed from the Sea; no a great part of them, viz. all that, when condenſed, waters the Earth, and ſerves for the Nutrition of Plants and Animals, (if not the ſame individual Water at leaſt ſo much) was exhaled out of the Earth before, and returned again in Showers and Dews upon it. So that we receive no more from the Sea, than what the Rivers carry back, and pour into it again. But ſuppoſing Mr. Halley's Hypotheſes to be good, and that the Ocean doth evaporate, and caſt off to the dry Land 1/10 of an inch thickneſs daily, and this ſuffices for the Supply of all the Rivers; how intolerably extravagant muſt their Hypotheſes be, who ſuppoſe the Rivers of all the World together to yield half an Ocean of Water daily? Though I muſt confeſs my ſelf to be at a loſs as to thoſe vaſt Rivers of America of ninety Miles broad; for if they ſhould run with any thing a ſwift Current, it is indeed ineſtimable what a quantity of Water they may pour forth. All therefore that I have to ſay of them is, that we want a true Hiſtory and Account of their Phaenomena from their Fountains to their Out-lets.
Pag. 72. lin. 29. and of Gravity;
I add alſo of Magnitude: which is exceedingly convenient, as well for the facility as the equability of the Earths diurnal motion. This Hypotheſis of the Continents being diſperſed equally on all ſides of the Globe makes theſe Centers concur in one Point, whatever cauſe we aſſign of the raiſing up of the Dry Land at the firſt. Whereas if we ſhould ſuppoſe the Dry Land to have been raiſed by Earthquakes only on one ſide of the Globe, and to have caſt off the Water to the other, and alſo that the Water could find no way into the Caverns that were left within; then the watery ſide muſt needs preponderate the land-ſide, and bring the Center of Gravity nearer to its Superficies; and ſo raiſe the land-ſide ſtill a great deal higher, and make a conſiderable diſtance between the Centers of Magnitude and of Gravity. In our Hypotheſis of the equal diſperſion of the Continents and Iſlands no ſuch thing would happen: but each Continent, taking it with all its internal Caverns, whether lighter or heavier than its bulk in Water, that is, Whether the Water did make its way into the Caverns thereof, or did not; (for in the firſt Caſe it would be heavier, in the ſecond lighter) would have its counterpoiſe on the oppoſite ſide; ſo that the Centers would ſtill concur. The Caſe would be the ſame if the Dry Land were diſcovered, and the Mountains raiſed by the immediate application of the Divine Power.
Pag. 94. after lin. 15. add,
Since the receipt of this Letter, an Experiment (give me leave ſo to call it) occurred to me, which much confirmed me in the belief and perſuaſion of the truth of thoſe Hiſtories and Relations which Writers and Travellers have delivered to us concerning Dropping Trees in Ferro, S. Thome, Guiny, &c. of which before I was ſomewhat diffident; and likewiſe in the approbation of the Hypotheſis of my Learned Friend Dr. Tancred Robinſon for the ſolving of that Phoenomenon. The ſame alſo induces me to believe, that Vapours may have a greater intereſt in the production of Springs even in temperate and cold Regions, than I had before thought. The Experiment or Obſervation is this,
About the beginning of December 1691. there happened to be a Miſt, and that no very thick one, which continued all day: the Vapour whereof, notwithſtanding the Trees were wholly diveſted of Leaves, condenſed ſo faſt upon their naked Branches and Twigs, that they dropped all day at ſuch a rate, that I believe the Water deſtilling from a large Tree in twenty four hours, had it been all received and reſerved in a Veſſel, might have amounted to a Hoggs-head. What then may we rationally conjecture, would have dropped from ſuch a Tree; had it been covered with Leaves of a denſe Texture, and ſmooth Superficies, apt to collect the Particles of the Vapour, and unite them into Drops?
It is clear by this effect, that Trees do deſtil Water a pace when Clouds or Miſts hang about them; which they are reported by Benzo conſtantly to do about the Fountain tree in Ferro; except when the Sun ſhines hot upon it. And others tell us, that that Tree grows upon a Mountain too: So that it is no wonder, that it ſhould drop abundance of Water. What do I ſpeak of that Tree? all the Trees of that kind grow on the ſides of vaſt Mountains, as Dr. Robinſon hath noted. Beſides that in hot Regions Trees may in the night time deſtil Water, though the Air be clear, and there be no Miſt about them, ſeems neceſſarily to follow, from Mr. Halley's Experiment.
Now if there be in Miſts thus much Vapour condenſed upon Trees, doubtleſs alſo there is in proportion as much upon the Surface of the Earth and the Graſs: And conſequently, upon the Tops and Ridges of high Mountains, which are frequently covered with Clouds or Miſts, much more, ſo much as muſt needs have a great intereſt in the production and ſupply of Springs, even in temperate Countries.
But that inviſible Vapours, when the Sky is clear, do at any time condenſe ſo faſt upon the Trees, as to make them drop, I never obſerved in England or elſewhere, no not in the Night-ſeaſon; though I do not deny, but upon the Appennine and Southern ſide of the Alps, and elſewhere in the hotter parts of Europe in Summer Nights they may. However conſidering the Penetrancy of ſuch Vapours, that in moiſt Wether they will inſinuate themſelves deeply into the Pores of dry Wood, ſo that Doors will then hardly ſhut, and Chinks and Crannies in Boards and Floors be cloſed up, I know not but that they may likewiſe ſtrike deep into the Ground, and together with Miſts contribute to the feeding and maintenance of Springs, in Winter-time, when the Sun exhales but little; it being an Obſervation of the Learned *Meteor lib. 5. c. 7. Artic. 3.Fromondus, Quod hyeme nec nivali, nec imbrifera fontes tamen aquam largiùs quàm aeſtate (niſi valdè pluvia ſit) vomant. That in Winters neither ſnowy nor rainy, yet fountains powre forth more Water than in Summer, unleſs it happen to be a very wet ſeaſon. Yet are their Contributions inconſiderable, if compared with the ſupplies that are afforded by Rains. And one reaſon why in Winter Fountains flow more plentifully may be, becauſe then the Sun defrauds them not, nor exhales any thing out of the Earth, as in Summer time he doth.
Therefore whenever in this Work I have aſſigned Rain to be a ſufficient or only cauſe of Springs and Rivers, I would not be underſtood to exclude, but to comprehend therein Miſts and Vapours; which I grant to have ſome intereſt in the production of them, even in Temperate and Cold Regions; and a very conſiderable one in Hot. Though I cannot be perſuaded, that even there they are the ſole Cauſe of Springs, for that there fall ſuch plentiful and long continuing Rains, both in the Eaſt and Weſt Indies in the Summer Months: which muſt needs contribute ſomething to their Original.
Pag. 169. lin. 19. add,
This end and uſe of Mountains I find aſſigned by Mr. Halley in his Diſcourſe concerning the Original of Springs and Rivers,Philoſ. Tranſ. num. 192. in theſe words: This, if we may allow Final Cauſes, (and why may we not? What needs this heſitancy and dubitation in a thing that is clear?) ſeems to be the Deſign of the Hills, That their Ridges being placed through the midſt of the Continents, might ſerve as it were Alembicks to diſtil freſh Water for the uſe of Man and Beaſt; and their heights to give a deſcent to thoſe Streams, to run gently like ſo many Veins of the Macrocoſm, to be the more beneficial to the Creation.
Pag. 170. lin. 10. add,
To ſumm up all relating to the Diviſion and Diſpoſition of the Water and Earth in brief.
1. I ſay, the Water being the lighter Element doth naturally occupy the upper place, and ſtand above the Earth, and ſo at firſt it did. But now we ſee it doth not ſo; the Earth being contrary to its nature forcibly elevated above it; being (as the Pſalmiſt phraſeth it) founded above the Seas, and eſtabliſhed above the Floods: and this becauſe it was beſt it ſhould be ſo, as I ſhall clearly prove and deduce in particulars in another Diſcourſe.
2. The Dry Land is not elevated only upon one ſide of the Globe; for then had it had high Mountains in the middle of it, with ſuch vaſt empty Cavities within, as muſt be equal to the whole Bulk raiſed up, the Center of Magnitude muſt needs have been conſiderably diſtant from the Center of Gravity▪ which would have cauſed a very great and inconvenient inequality in the Motion of the parts of the Earth: but the Continents and Iſlands are ſo equally diſperſt all the Globe over as to counterballance one another, ſo that the Centers of Magnitude and Gravity concur in one.
3. The Continents are not of exactly equal and level Superficies or Convexity. For then the Parts ſubject to the Courſe of the Sun, called the Torrid Zone, would have been, as the Ancients fancied them, unhabitable for Heat and Drought. But there are huge Ridges and extended Chains of lofty Mountains, directed for the moſt part to run Eaſt and Weſt; by which Means they give free Admittance and Paſſage to the Vapours brought in by the Winds from the Atlantick and Pacifick Oceans; but ſtop and inhibit their Excurſions to the North and South, either condenſing them upon their ſides into the Water, by a kind of external Deſtillation; or by ſtreightening and conſtipating of them compelling them to gather into Drops, and deſcend down in Rain.
Theſe are great things, and worthy the Care, Direction, and Diſpoſal of the Great and Wiſe Creator and Governor of all things: And we ſee they are accordingly excellently ordered and provided by him.
Some Greek and Latin Quotations Engliſhed.
Pag. 25. Lin. 7.
THoſe Words of Lactantius, Ergo quoniam ſex dierum, &c. ſignifie in Engliſh, Therefore becauſe all the Works of God were perſected (or finiſhed) in ſix days, it is neceſary (or neceſſarily follows) that the World ſhall continue in this State ſix Ages, that is ſix thouſand years▪ For the great Day of God is terminated in a Circle of ſix thouſand years: as the Prophet intimates, who ſaith, A thouſand years in thy ſight, O Lord, are but as one day.
Pag. 26. lin. 25.
foreign, &c. He acutely calls the Death of the Elements their change into better.
Pag. 32. Lin. 18.
Cùm tempus advenerit, &c. When the time ſhall come, that the World again to be reſtored (or to recover it ſelf) ſhall periſh, theſe things ſhall beat or mall themſelves by their own ſtrength, the Stars ſhall run, or fall foul upon one another; and all the matter flaming whatever now ſhines according to its ſettled Order or Diſpoſition ſhall then burn.
Pag. 33. lin. 25.
Reſoluto mundo & Diis in unum confuſis. When the World ſhall be diſſolved, and the Gods confounded into one. Atque omnes pariter Deos perdet Nox aliqua & Chaos. And in like manner a certain Night and Chaos ſhall deſtroy all the Gods.
Pag. 34. lin. 10.
foreign, &c. That there ſhall ſometime be a change of the World into the Nature or Subſtance of Fire.
Pag. 36. lin. 5.
foreign, Then God not mitigating his anger, but aggravating it, ſhall deſtroy by fire the whole Race of Mankind.
Pag. 5. lin. 45.
In plenum, &c. In ſumm, it is obſerved, that the meaſure of all Mankind becomes daily leſs, and that there are few taller than their Parents, the burning heat conſuming the Luxury of the Seeds. Ibid. Terra malos, &c. The Earth breeds now Men bad and ſmall.
Pag. 107. lin. 20.
Non procul, &c. Not far from the Mountain called Paterno, where the Bononian Stone is gotten, about an Italian Mile diſtant, (the name of the place is ſlipt out of my memory) is a huge hanging Mountain, broken by the violence of the Torrents, cauſed by the confluence of Waters deſcending from the Neighbouring Mountains after frequent Showers, throwing down great heaps of Earth from it. In the upper part of this broken Mountain are ſeen many Beds or Floors of all kind of Sea-ſhells, much Sand interpoſing between Bed and Bed, after the manner of ſtratum ſuper ſtratum, or Layer upon Layer, as the Chymiſts phraſe it. The Beds of Sand interceding between theſe Rows of Shells were a yard thick or more. Theſe Shells were all diſtinct or ſeparate one from another, and not ſtuck in any ſtone, or cemented together, ſo that they might be ſingly and ſeparately viewed and handled with ones Hands. The Cauſe whereof was their being lodged in a pure Sand not intermixt with any Mud or Clay, which kept the Shells entire for many Ages. Yet were all theſe Shells, by reaſon of the length of time they had lain there, eaſily reſoluble into a purely white Calx or Aſh.
Pag. 133. lin. 17.
Prodigioſi, &c. Prodigious and laſting Defects of the Sun, ſuch as happened when Caeſar the Dictator was ſlain, and in the War with Anthony, when it was continually pale and gloomy for a whole year.
Pag. 185. lin. 5.
Ego non audeo tempora dinumerare, &c. I dare not calculate times, neither do I think, that concerning this matter any Prophet hath predicted and defined the Number of Years: What therefore the Lord would not have us to know, let us willingly be ignorant of.
FINIS.