SECT. IV. THE Cause of their Coldness is, 1. A Mixture of Nitre and Alum, alfo of Mercury and Iron, &c. 2. The great Depth from whence they spring, fo that they want the Rays of the Sun, and the fulphureous Heat under Ground. THERE are alfo Fountains that are cold and hot by turns. In Catalonia there is a falt Fountain and Lake, which are extream hot in the Winter and as cold in Summer. This is common to several others. I fuppofe the Cause of it is, that the Pores of the Earth, being open in Summer, let out the fubterranean hot Spirit thro' them which being fhut in during Winter, keep it as in a Furnace or Oven, to warm the Water. Thus fome Fountains are hotter in the Night than in the Day. PROPOSITION XI. To explain the Origin of thofe Waters that seem to turn Bodies into other Species; and to enumerate the Places of the Earth in which they are found. THERE are fome Waters which petrify Wood or turn it into hard Stone. A little above the City of Armagh in Ireland, there is a small Lough, in which if a ftick of Wood be fixed, and continue for fome Months, the Part that is faft in the Mud becomes Iron, and that in the Water turns to a Whetstone, and that above Water continues to be Wood. This is reported by Giraldus and Maginus: but Brietius, by what authority I know not, fays that it is a Fable throughout (g). (g) There is certainly no fuch Lough as this in Ireland; their famous Lough Neagh was formerly thought to have a petri In fying quality; but upon due examination it is found, that the faid quality is to be ascribed to the Soil of the Ground adjacent to In the North Part of Ulster (a Province in Ireland) there is a Fountain, in which if Wood be immersed seven Years it will be petrified. There are Loches of Water in the Province of Beauffe in France, that petrify every thing thrown into them. At the Town of Sens in [Champagne] near to the Lake, rather than to the Water of the Lake itself. There are fome Waters in Scotland that petrify: As in Glevely, at a Place called Achigniglium, there is a Rivulet which so turns Holly into a greenish Stone, that they ordinarily make Moulds of it for cafting of Balls for Fuzees; and Tinkers that work in Brafs, make both their Moulds, and melting Pots of it, and Women their round Wharls for spinning. Alfo upon the north Side of the Firth of Forth there is a Cave, from the Top of which drops Water that in falling makes long Columns refembling the Pipes of a Church Organ, and fome of different Figures. See Philof. Tranf. abridged by Lowthorp. Vol. 2. Page 321, 325. • There is a River in Thrace which if you • drink of it, will turn your Bowels into Stone, and cafes 'with Marble whatever is put ' into it. Concerning which Seneca thus fpeaks in his Natural. Queft. Book 3. Chap. 20. the • Mud of it is of that Nature that it glues Bodies together, and hardens them. As the Duft of • Puteoli, if it touches the Water, it becomes Stone, fo on the contrary, this Water, if it touches any thing folid, fticks, and cleaves to it. Hence it is that Things thrown into this ་ Lake are afterwards taken out and converted into Stones. The fame Thing happens in • fome Parts of Italy, if you put in a Rod or a green Leaf, in a 'few Days after, you take out a Stone. And Pliny Book 2. Chap. 103. fays, In the 'Cicous River, and in the Lake of Velinas, in the Country of Marca di Ancona, Wood caft in is covered over with aftony Bark, and alfo in Surius a River in Colchis; fo that a hard Bark commonly covers over the Stone ftill. So likewife in the River Silarius, beyond Sarrentum, not only Rods put in, but also Leaves turn into Stone; the Water is other⚫ wife very wholesome to drink. Clarke upon Robault's Phyf. Vol. 2. Pag. 202. In the Island of Haynan near China there is a Water of fuch a strange quality that it petrifies fome fort of Fishes when they unfortunately chance to enter into it. Among the Quickfilver Mines in Guianavilica in Peru, is a Fountain of hot Water whofe Current having run a confiderable way, turns at laft into a foft kind of Rock, which being eafily cut, and yet very lafting, is ufually employed for building of Houses thereabouts. There are feveral petrifying, and incruftating Waters in Virginia, &c. a Lake, Vi SECT. IV. a Lake, there flows a petrifying Fountain. truvius tells us that there is a broad Lake, between Mazaca and Tuana in Cappadocia, which changes a Reed or a stick of Wood, in one Day, into Stone. There is a Fountain near Charles's Baths in Bohemia, in which if Wood lie long it is turned into Stone. Such as these are found in divers other Places. Other Waters are thought to change Iron into Copper, which in fact they do not, only because these Waters carry the Spirit and Particles of Vitriol and Copper, they eat out, and by little and little diffolve, the Particles of Copper as they flow along with the Water. THE Caufe why these Waters turn Wood into Stone is, 1. Some do not change the Wood itfelf into Stone; but the earthy, ftoney, faline Particles contained in the Water stick to the Wood, and only incruftate it with a ftony Crust. 2. Others do not change the Wood into Stone, but give it a hardness equal to that of Stone. 3. If any Water have a true petrifying Quality, I fuppose it may be accounted for thus (b). The chief 6 Difference Twigs, and Mofs laid for that Purpofe on the Edge of it, it is diffused all over the Stone, and partly gleets down the fides, and partly falls perpendicularly in Drops upon fome Pebbles, where there is a small Matter of Water below. • This Well doth by no means petrify Wood, Mofs, &c. put into it, but only incrufts them 'all over with a ftony Cruft; • Neither hath it this incrusting quality (at the Spring Head) before it comes to the Break, and runs down, or drop, from the soft marly Stone. Difference that can be perceived by the Eye between Wood and Stone is, that in the Wood there are as it were long Fibres in which it's Parts cohere, tho' not very close. But in Stone the Particles, being as it were Sands or Atoms, are not joined by any extended Fibres. If therefore it be the Nature of any Water to diffolve, and, as it were, grind the long fibrous Particles of Wood, that they do no more cohere after this Manner, but are ftill more condensed, the Difference between it and Stone will not be fo great as to be difcerned by the Eye; yet it is probable that these I am the larger upon this, because it seems to point out the true Reafon of Petrifaction; for is it not hence reasonable to fuppofe? that the Water gleeting down the fides of the to be acted upon by Fire: but if (as in the present Cafe) the Particles are not fo minute as to penetrate the Pores of the 'Wood, they only stick close to the outfide of it, and parget foft Stone, corrodes the minu-it over (as it were) by degrees teft of it's Particles, and is impregnated with them; which are again feparated from the Water, by putting sticks of . Wood into it, (by the Power • of Attracting) as we see some kinds of Salt separated from . Water by the like Means, and other Bodies separated from those that are compounded with them, by fuch as are found by Experience to attract their Particles. Now when thefe Particles are fo minute and fubtile, as to intrude with the Water into the Pores of the Wood, in process of Time, when it is throughly foaked, the Interftices will be quite • filled with ftony Particles; and if any thing ligneous remain, it is fo well guarded and incruftated by these Particles that it is not perceptible, nor to a confiderable thicknefs. • What strengthens this Opi'nion very much is ; that the Particles of the Case or Cruft, ⚫ when ground to powder, are, to all appearance, like the Particles of the Stone from whence the Water drops, only the later is fomething whiter and rounder. Is not therefore fuch fub'terraneous Earth as this, thro' which the Water, of fuch like Qualities, runs, the Cause of • Petrifaction? 6 • Because we may gather 'from hence the Reasons why Fountains petrify fome forts ⚫ of Wood throughout, but not others; alfo why fome petrify only the Bark, Sap, or fofteft Part, and others only incafe it, &c. mineral mineral Waters communicate fome Substance even to Wood itself. PROPOSITION XII. To explain the Caufe of poisonous or lethiferous Waters; and to enumerate the Places of the Earth in which they are found. THE Lake Afphaltites is one of thefe, having Arfenic mixed with Bitumen in it (i). The Fountain of Neptune, near Terracina in the Country of the Volfcians was famous of old, because all that drunk of it immediately loft their Lives; and therefore it was filled up with Stones by the Inhabitants. At Chycros in Thracia there was a Lake that killed not only thofe who drunk of it, but even thofe that washed in it. There is a Fountain in Theffaly which Cattle are not fuffered to tafte, nor any kind of Beast to come near it. Vitruvius relates, that there is fuch deadly Water as this near the Sepulchre of Euripides in Macedonia. As to the Spring and River Styx in the (i) Near Efperies in Upper Hungary are two deadly Fountains whofe Waters fend forth fuch an infectious Steam that it kills cither Beaft or Bird approaching the fame; for the preventing of which they are walled round and kept always covered. In Ireland there is a Lake which commonly fends up fuch a peftilentious Vapour, as frequently kills Birds that endeavour to fly over it. Near • Dantzic there is an inland Sea made by the Confluence of three Rivers, whofe Waters are Sweet and wholefome, and well ftored with delicate Fish; yet in the three Summer Months, June, July, and Auguft, it becomes every Year green in the middle with an hairy Efflorescence; which green Substance being by fome violent Wind forced afhore, and with the Water drunk by any Cattle, Dog, or Poultry, caufeth certain and fudden Death'. See Mr Kirkby's Obfervations upon it in Philof. Trans. No 83. Beyond the Falls of Rapahanac in Vir ginia there are faid to be poifonous Waters, &c. Mountain |