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334

SIR,

ONE

Eye IVitnesis of Toads in Stones.....Dr. Thompson. To the Editor of the Monthly Magazine. that are found alive in stones : in Toulon

Harbour, and the Road, are found folid NE of your late correspondents has hard stones and perfe&tly entire, contain

called in question the truth of all ing, in different cells, fecluded from all the accounts you have given respecting communication with the air, several liv. toads having been found alive in the ing theli fish of an exquisite taste, called middle of fones : and he rests his ob- dactyli, or dates. To come at these fish, jection on the ground, that the various the stones are broken with mallets. relations have all' been given at second

Also along the coast of Ancona, in the band. He calls for one from an eye-" Adriatic, are stones, usually weighing witness! Let him take the following, about fifty pounds, and sometimes inore, given by Ambrole Pare, chief furgeon the intide fo compact and firm as to re

the outside rugged and easily broken, but to Henry III. king of France, and a man of confiderable information and abi- quire a strong arm and an iron mallet to lities.

break them. Within them, and in sepa“ Being (says he) at my seat near the rate apertures, are found finall shell fish village of Meudon, and overlooking a quite alive, and very palateable, called quarry-man, whom I had set to break fole nas, or cappe lunghe. These facts are

very large and hard ftunes, in the attested by Gassendi, Blondel, Mayol, middle of one we found a huge live toad, the learned bishop of Sulturara, and more though there was noʻvisible aperture by particularly by Aldrovandi, a physician which it could have got there.

I could of Bologna. The two latter speak of it not help expressing my wonder how it

as a commonly known fact, and of which had been generated, had grown, and they themselves were

EYE WITNESSES. lived; but the labourer told me, it was not the first time he had met with toads and the like creatures within huge blocks For the Monthly Magazine. of stone, in which there could he found

CURSORY no visible opening er fiffure.”

OBSERVATIONS upon the Your doubting correspondent may find

SILICEOUS INCRUSTATIONS of ĮTAsimilar relations given by eye witnefles,

LIAN HOT SPRINGS, and particularly if he will consult Baptista Fulgota, doge

on those of the CAMPI PALEGRÆI," of : Genoa; Agricola, Horstius, Lord

in the Kingdom of Naples. Verulam, &c.

By Dr. THOMPSON, of Naples., - In the volume for 1719 of " The Transactions of the Academy of Sciences, at (i

(1) THE

THE filiceous deposition of Gey. Paris,” the following is given :

fer, in Iceland, is become gene** In the foot of an elm, of the bigness of rally known, since the analysis of it by a pretty corpulent man, three or four feet Bergman. (2) In the succeeding auabove the root, and exactly in the center, tumn of 1791, I communicated to the has been found a live toad, iniddle-fized, but Journal de Physique, of Paris, my havlean, and filling up the whole vacant fpace. ing found similar incrustations produced No íconer was a panage opened, by splitting from the warm waters of the Lakes of the wood, than it scuttles away very haftily: Sasso, in Tuscany. (3). From thence that the toad can not be fupposed to have set travelling by the Montamiata of Tut: into it: the egg, whence it was formed, muit, cany, on the mountain of Santa Fiora in by some very fingular accident, have been the same autumn, I found there small lodged in the tree at its first growth. There filiceous stalactites, transparent and bright the creature had lived without air, feeding as rock, crystal, inclosed in the cavities of on the fubstance of the tree, and growing only a very hard lava, which on the flightest as the tree grew,.”

application of fire, became opaque, and This is attested by Mr. Hubert, pro- appear like pearls. (4) Passing the winfessor of philosophy at Caen.

ter of 1791 at Florence, there occurred In the volume for 1731, M. Seigne, of to my obiervation a small specimen of a Nantes, lays before the Academy a fact similar stalactite shut up in the cavities of just of the very fame nature, excepting a certain hard lava of the Euganian thai, instead of an elm, it was an oak, of mountains in the Vicentine; and aftersuch a size, that judging by the time wards I acquired a specimen of impure neceffary for its growth, the toad must magnesia,' called, at Florence, gabbro, have fubfifted in it without air or aliment coming from Impruneta, which specimen during 80 or 100 years.

is coyered over with similar stalactites, or But toads are not the only animals little pearls, which become bright and

opaque

Dr. Thompson, of Naples, on Siliceous Incrustations. 335 opaque on the application of the flame of a found there some time before; he fuclamp; which proceed from the multiplied ceeded in his object, and carrying with crevices or divisions, which in such case him Tome fpecimens of it to Naples, I extend themselves in every direction in had the pleasure to observe likewile, in this substance: in the fame manner as them, filiceous fialactites; these contained, transparent ice and glass, when pounded, however, filiceous veins, but larger, as become white : which indeed Faujas de well white and opaque as glasly, in this Saint Fond seemed not to have considered case existing in a substance more compact. when he propofes to us his difficulties (7) Being now aware of the frequency of relative to the cause of the pearly bright fuch phenomenon, and seeking for it in ness which he describes in similar stalac-' the autumn of the same year, I found tites, in page 330 of his “ Mineralogie likewise these filiceous incrustations semides Volcans, 8vo. 1784*, If, however, opaque, and white in decomposed lava, these divisions become excessive, then the which chietly forns the external fides of white is rendered perfectly opaque instead the ancient volcanic crater, now called of the shining lustre of mother of pearl, the Zolfatara di Pozzuoli; hence I conand the stalactite too much cracked, crum- jectured it would not be difficult to find bles between the fingers. I likewise ob- the same also within this crater, at preient tained, in the winter, in exchange with exhausted, except that there are yet fome the Ducal cabinet of Florence, a little tunnels in activity, and that sulphur is piece of that more beautiful mamillonate daily formed there in abundance ; returnstalactite of the Montamiata, presented ing then again in this present autumin, I to me, together with other specimens, found the laid phenomena under a great by the discoverer himself, Professor Gior- many varieties, some of the stalactite bea gio Santi, of Pisa; , and in March 1792, ing resplendent, and others variegated; the respectable professor shewed me and fome of the specimens were of a pale presented to me, other pieces of this his white colour and opaque, others thining pearled filiceous stalactite, considerably like glass; sometimes inc. enfing the larger, and more beautiful than those í fuperficies of the decompofue lava, at had, until then, met with; and I then other times cementing the fragments of learnt, that those observed by me the the same, reducing them to the appearpreceding autumn, in the Montamiata, ance of folie, and extremely hard itone. were likewise not unknown to him. At length I perceived, now for the first (5) Travelling in the year 1794, in the time, that on all occafions where occur island of Ischia, I found many of those sinall extensive surfaces of such incrustations, and most brilliant filiceous stalactites, they are expressly those, which, stretching together with other white ones grouped themselves out like paint, cover over and in the veins and crevices of the pumice, defend the yielding ani pliable white scattered among the porous kind of stone earth there prevailing, which is nothing which had been recently cut through, to elie than lava decomposed by vapours, form an ascent from Lacco to the baths and which, without this defence, would of San Lorenzo; as also in the filiceous be carried totally away by the torrents of veins of another little rock of the same rain which fall upon it. substance near the sea at Lacco, being In these filiceous fuperficies, which exactly that upon which there is a lime will often deceive not the eye only, but kiln. I communicated these observations the hand armed 'with the hammer, so as the same day to Abbate Breislak, who to induce the opinion, that the substance collected numerous fpecimens of it for his beneath the incrustation nay likewise be friends. (6) The fame Abbate Breillak, very hard; I do not recollect other than after my return to Naples, dug in a the ancient crevices of the lavin, which place still lower than the before mentioned rendered it permeable to those pours, afcent, with a view to meet with sulphur, which have now destroyed ii, by louding which some persons asserted to have been the whole ípace of this pastage with fili

ceous earth, already held in folution. * The pearls here described by Faujas be- fervation to be regarded among the most

If my surprise was great, that an obing the same with those of the Montamiata, and being of volcanic origin, as are likewife predominant of this place, should have so many others to be named hereafter, in- escaped the remark of preceding minercreases the probability that the basalts where alogists, who expreis themselves with the pearls of Faujas are imbedded (“ Glas much warmth upon the initructive, pleno. Hyalites of Müller), may be indeed of volcanic

mena of the Zolfatara, I trust the accuorigin, which some have hitherto doubted. fation of envy ought not to be attached

MONTHLY MAG. No, XXXI.

xx

to

336

caca

Dr. Thompson, of Naples, on Siliceous Incrustations. to this refle&tion, when I confess that I time as the sulphur. I went, therefore, have been astonished at my own blindness in company with Count Redern, to a much more than at the omission of others, place called Monticeto, above Casamic. having myself already more than once ex- ciola, and there on the side of a channel amined the Zolfatara, without having produced by torrents, but then dry, we been arrested for a moment by the above- inet indeed with humid vapours, which recited phenomenon, which would appear caused the thermometer of Fahrenheit, the impossible, since it presents itself under so bulb of which was placed in the holes many points of view. Let another na- from whence the vapours escaped, to aftural philosopher answer for me :

cend to 202; and judging from the rapid “Hæc fi pernofces, parva perfunctus opella, elevation of the mercury, I believe the rise (Nanique aliud ex alio clarescet) non tibi would have been considerably more in a

thermometer whose scale was more exNox iter eripiet, quin ultima naturai tensive: but mine being calculated for Pervideas, ita res accendunt lumina rebus!" experiments upon the heat of animals;

Lucret. lib i. did not permit us this proof, terminating (8) In July of the present year, coast a few degrees beyond that of boiling ing the edge of the vast clett, whence was water, or 212. vomited the immense lava, which the last We did not find there either fulphur year ruined, in a few hours, the populous or hepatic air, but we perceived the limell town, Torre del Greco, I remarked there of something burning, which I have althe volcanic fand, partly red, partly ways found to accompany such orifices, green (ihorl), as though it had been pow- and that rather resembles the odour of dered with hoar frost, which, to the eye burning fulphur, but weak and much would have appeared a faline substance; attenuated. The rock whence proceeded but this likewise is nothing else than a these vapours, is a greenish tuta, rich in most fubtle plaister, or filiceous varnish, magnesian earth, and in little pumice which covers over this tand, whose pro- stones, the whole corroded by moisture, minent grains inclining to a circular form, and of consequence extremely tender. have the appearance of so many little Around the orifice, but always at a small pearls. This fubtle and tender crust, distance, and upon the sides of the little on the application of water, becomes cavern, we met with various incrustations hydrophanous and transparent, whence resembling efflorescences, produced there the eye, although experienced, easily by the vapours: it will be sufficient to paflus it unobserved. The fand, con

notice glutinated in part by those incrustations, 1. Chalk of a foliated form, abundant. and in part by its calx of iron, forms a 2. Alurn, but feldon, and in small kind of fuperficial mirror of little consift-' quantities. ency upon the ashes.

In other places

3. Siliceous stalactites, foliated, cylin-. around the new openings of the mountain, drical, or conical and pendent (mamillonate), a similar crust is found, less bright, but very brittle, and of littie confiftence; on thicker, which alsumes the form of ita- touching the tenderest points of it, which lactites, and recruits itself with the of their filiceous hardneis.

crumbled between the teeth, I was first aware Jarger volcanic fragments. It is obfervable, that in all these places, open- hereafter. (Sec. 19.)

4. A bitter salt, of which I fall speak ings, from whence escape humid and scalding vapours, are frequent even at in the bottom of the channel itself, we

Afterwards, lower down the steep and present. (8) Returning into Ischia in August

found siliceous crusts, less delicate, but of the present year, and invited to visit

more compact than those before mentioncertain outlets of hot vapour, and as I ed, and sometimes coloured with red: was assured, of hepatic air, 1 conceived there are also fome veins of the fame from hence the possibility of finding there fubftance, which indicate the site of other also, fulphur, which might tend to elu- afterwards a few inches within the mouth

orifices already exhausted. Penetrating cidate the generation of that sulphur of the orifice now in activity, we found, found by Abbate Breitlak (1. 6.) in a

three place where the vapours no longer exist

. lactites, of a mamillonate form, tender,

of very white siliceous ftaThe presence of filiceous incrustations, and io hot as not to permit us to retain together with the fulphur already mentioned (f. 6.), would likewise deserve

them in our hands. (10.) Since then, by fome contideration, as these had all the employing much diligence, I have succharacter of being produced at the fame ceeded in finding fulphur mixed in the

substance

Dr. Thompson, of Naples, on Siliceous Incrustations. 337 substance of those greater stalactites of the abundance, that it being impossible it Montamiata, as we have indeed already should have been an error, it is necessary noticed in those specimens found in Ischia, to believe, that not only mineral alkali, by Abbate Breillak (f. 6.), and as ap- but likewise also marine falt, exists efpear more clear in thole specimens of hili- fectively in the live cane; because, with ceous Italaclite, transparent as glass, this view I collected the canes in the val. found afterwards in the above stated visit ley between the crater of Aftruni and that to the Zolfatara di Pozzuoli (1.7.), when, of the Zolfatara, which is separated from together with Count Redern, I had the the sea by the whole elevation of the Zolfortune to inform myielf of the pheno- fatara, and by other circumjacent hills, mena already recited, and besides that, which removes the suspicion that the to find sulphur and filiceous stalactite to marine falt could be scattered by the sea intimately combined, that there is no breezes, and had fallen upon the canes : longer a doubt of their being produced this caution I took for greater security, together ; deriving their common origin because such a suspicion undisputed,would from warm and humid vapours, and hence have produced other difficulties, and those denominated by me thermal: and here not trivial. (14.) It is known, however, I obterve, that the moisture apparent in most incontestibly, that almost, if not all, drops near the fulphur produced from the the thermal waters of Ischia, abound Zolfatara, is loaded with vitriolic acid, with mineral alkali, both free, and united while those drops which distil round with marine acid; it is found also in both about the filiceous stalactites of Monticeto, states attached to the rock, above the where there is no palpable fulphur, are spring called Gorgitelio, which furnithes inlipid, and devoid of Imell.: (11.) At its waters to the baths of the neighbourprelent, we know that Professor Black, ing beautiful hospital. We are affured of Edinburgh, analizing the waters of that the said mineral alkali has been Geyser, discovered in them the presence found, although in one place only, of the of mineral alkali, the known folvent of Zolfatara of Pozzuoli, that is, in the siliceous earth, put into acìion by means glauber falts. See Breislak fulla Zolfat. of fire, or in the dry way. See Philos, (15.) The presence of mineral alkali in Trans. of Edinb. (12.) We know, like the humid vapours of Vesuvius, will not wise, that in the junctures, or knots of be disputed by any one who knows how the cane called bambov, filiceous earth is frequent is inarine falt crystallized in found, pure, and concrete, and of fuch cubes, among the falts produced from hardness as to scrape glass. See Macie such vapours as well in the laft as in other upon Tabafhver in ihe Philos. Trans. of eruptions : nevertheless the orifices, howLondon. (13.) This moit interesting ever small, which now sublift on the spot. addition to our knowledge upon the power where are found the little Vesuvius pearls, always existing in the live cane to retain mentioned (sec. 8.) fuffice to bring to our filiceous earth in a state of liberty, ex- recollection the excessive quantity of such cited me to seek that mean which seemed vapours which evolved themselves on thoie to me best adapted to such folution, I horrible days, when exploded from the mean mineral alkali in the fresh juice of abyss, the viscera of the earth disfigured fome plant which might most resemble and changed in their nature by fire, were the bamboo, and for this purpose, I took seen to melt like glass; a subject of most the common cane of this kingdom (arun- interetting contemplation to the minerado donax (rofeau), and intuting into its logist, not, however, unmixed with apjuice fome few drops of fpirits of sea salt, prehenfion, while he beheld loaded vines, I gained, by flow evaporation, little cubes cities, the fruits of human ingenuity, overof marine salt, a proof of the presence of thrown and utterly destroyed. (16.) The mineral alkali which I sought for. origin then of these filiceous Italactites,

Suspecting the purity of the acid I whether transparent or subdivided and had employed, which might perhaps hold shining with a pearly brightness, appears mi solution marine salt already formed : to depend on no other cau"- than the fo. to convince myself inore fully, I exposed lution of filiceous earth by m. ns of mia to flow evaporation the decoction of the neral alkali, and by the humid w ży, that Taid juice, made with distilled water as is, by humid vapours rendered a&tive by before, without any infusion of spirit of excess of fire. (17.) The place from marine falt; but it happened to me to dif- whence these vapours escape, becoming cover, what eyen until now I have been charged from time to time, it becoines unable to explain, that is, to find cubes probable from this (sec. 9.), that the staof lea falç allo this time, and in such lactites found beneath the hot bath of

X X 2

San

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Dr. Thompson, & c.....Utility of Prebendaries, &c. San Lorenzo, derive their origin from the 5. Although the orifices of Monti. same vapours, which at this time supply ceto, and of Ischia, have not as yet afforded thele baths; and that their subterraneovis actual fulphur, there are, nevertheless, arches will be found in process of time sufficiently plain indications of it, in the laden with fimilar depositions. This, as presence of vitriolic acid existing as well has been already noticed, has happened in the alum as in the chalk found there in the Zoiratara of Pozzuoli (1. 7.). (f. 10.); and also in bitter salt, both that (18.) The filiceous stalactites above re with a magnesian base, Epsom falt; or ferred to of San Lorenzo, imbibed them- with a bate of mineral alkali, glauber felves (i. 5.) in pumice, and those only falt, or finally of vegetable alkali, which of Monticelo (1. 9.) are adherent to a laft salt, vitriolated tartar, so frequent decompored pumice rock; it may be upon the lavas which have destroyed the added, that those greater ones of Monta- plain, is not unknown in the highest parts miata are found also in a friable granite of Vesuvius, since I have found it three rich in small pumice-stones ; 'or crystals years ago distilling from the cone, itself, of Feldipar íwelled and cracked by fire, half way from its base, from some mouths and hence become fluid, as far as the en whence small stream of lava has protire mais of granite is capable of becom- ceeded, at no remote period. This salt ing; as has been already observed before afterwards became so hard, forming me by Count Dolomieu, and has been il- opaque masses, similar to marble, that it at luttrated by him in his Voyage to the Illes firit gave little fufpicion of its true naof Ponza.

ture; and, in fact, I have seen it described Indeed, when I saw by means of the in collections, as stones of Vesuvius. lens that this granite incloses often in its With regard to the bitter falt of fibrous vein, produced as already stated, Monticeto (f. 10.), its scarcity has not the minutest "liliceous and transparent permitted us as yet to ascertain its preftalactites, at first I hesitated to believe cise nature. that they were owing strictly to the dry The preceding observations, therefusion of feldspar; but since that I am fore, fo nearly correspond, as in effect to become acquainted with vapours, humid teach us, that wherever these filiceous and saline, already formed or growing stalactites have hitherto been found, we from thin elements reciprocally in ac- likewise meet with humid and warm tivity, intimately diffused through the vapours, with mineral alkali, often demass of ignited and running lava, and re- monstrated (f. 11. 14. 15.), and whose preflecting how much so spungy a granite sence is always to be fufpected, as the is penetrable by such vapours, I quit my generative cause of these stalactites, with firit idea as superfluous, if not erroneous; the intervention also of fulphur, either in exposing 19y own dificulty as a greater substance, or manifested in its product, caution to him who wishes to follow with which is vitriolic acid, as soon as fulthe neceffary accuracy this argument. It phur, in an aëriform state, comes in condoes not appear to me, that the faid sta- tact with the atmosphere, whence it atlactites have actually their origin from tracts that dose of pure air which it repumice in preference to the other filiceous quires to enable it to assume its new prosubstances composing such rock, but be- perties. cause the pumice may have presented to the foivent vapours a superficies the most Parthenope ftudiis florentem ignobilis oti. multiplied, and, on that account, the most capable of being generally attacked. (19.) Belides this, it may be noted

To the Editor of the Monthly Magazine. fo far as regards sulphur, that

SIR, 1. Some warm springs in the vicinity OUBTS have been sometimes enterof Geyfer give us filiceous depositions tained by men who are in the habit mixed with sulphur.

of thinking for themselves, concerning 2. The little lakes of Sasso in Tur- the utility of some classes of dignitaries cany produce fulphur.

in our church, particularly deans and 3. Vesuvius in activity gives sul- prebendaries. The opinion of an archphur.

bishop, therefore, upon this subject, muft 4. The filiceous stalactites of the have considerable weight: and the followMontamiata, those found by Abbateing curious obfervations, on the advan. Breillak in Ischia, and, finally, those of tages resulting from prebendaries to relithe Zolfatara di Pozzuoli, are all mixed gion and learning, are contained in a let. with fulphur..

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