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You taste the cooling breeze, where nearer home
Then briny seas and tasteful springs farewell,
Where fountain-nymphs confused with Nereids dwell,
The natural curiosities about Naples are as numerous and extraordinary as the artificial. I shall set them down, as I have done the other, without any regard to their situation. The grotto del Cani is famous for the poisonous steams which float within a foot of its surface. The sides of the grotto are marked green, as high as the malignity of the vapour reaches. The common experiments are as follow: A dog, that has his nose held in the vapour, loses all signs of life in a very little time; but if carried into the open air, or thrown into a neighbouring lake, he immediately recovers if he is not quite gone. A torch, snuff and all, goes out in a moment when dipped into the vapour. A pistol cannot take fire in it. I split a reed, and laid in the channel of it a train of gunpowder, so that one end of the reed was above the vapour, and the other at the bottom of it; and I found, though the steam was strong enough to hinder a pistol from taking fire in it and to quench a lighted torch, that it could not intercept the train of fire when it had once begun flashing, nor hinder it from running to the very end. This experiment I repeated twice or thrice, to see if I could quite dissipate the vapour, which I did in so great a measure, that one might easily let off a pistol in it. I observed how long a dog was in expiring the first time, and after his recovery, and found no sensible difference. A viper bore it nine minutes the first time we put it in, and ten the second. When we brought it out after the first trial, it took such a vast quantity of air into its lungs, that it swelled almost twice as big as before; and it was perhaps on this stock of air that it lived a minute longer the second time. Dr. Connor made a discourse in one of the academies at Rome upon the subject of this grotto, which he has since printed in England. He attributes the death of animals, and the extinction of lights, to a great rarefaction of the air, caused by the heat and eruption of the steams. But how is it possible for these steams, though in never so great quantity, to
resist the pressure of the whole atmosphere? And as for the heat, it is but very inconsiderable. However, to satisfy myself, I placed a thin vial, well stopped up with wax, within the smoke of the vapour, which would certainly have burst in an air rarefied enough to kill a dog or quench a torch, but nothing followed upon it. However, to take away all further doubt, I borrowed a weather-glass, and so fixed it in the grotto, that the stagnum was wholly covered with the vapour, but I could not perceive the quicksilver sunk, after half an hour's standing in it. This vapour is generally supposed to be sulphureous, though I can see no reason for such a supposition. He that dips his hand in it, finds no smell that it leaves upon it; and though I put a whole bundle of lighted brimstone matches to the smoke, they all went out in an instant, as if immersed in water. Whatever is the composition of the vapour, let it have but one quality of being very gluey or viscous, and I believe it will mechanically solve all the phenomena of the grotto. Its unctuousness will make it heavy, and unfit for mounting higher than it does, unless the heat of the earth, which is just strong enough to agitate and bear it up at a little distance from the surface, were much greater than it is to rarefy and scatter it. It will be too gross and thick to keep the lungs in play for any time, so that animals will die in it sooner or later, as their blood circulates slower or faster. Fire will live in it no longer than in water, because it wraps itself in the same manner about the flame, and by its continuity hinders any quantity of air or nitre from coming to its succour. The parts of it, however, are not so compact as those of liquors, nor therefore tenacious enough to intercept the fire that has once caught a train of gunpowder, for which reason they may be quite broken and dispersed by the repetition of this experiment. There is an unctuous clammy vapour that arises from the stum of grapes, when they lie mashed together in the vat, which puts out a light when dipped into it, and perhaps would take away the breath of weaker animals, were it put to the trial.
It would be endless to reckon up the different baths to be met with in a country that so much abounds in sulphur. There is scarce a disease which has not one adapted to it. A stranger is generally led into that they call Cicero's bath, and several voyage-writers pretend there is a cold vapour
rising from the bottom of it, which refreshes those who stoop into it. 'Tis true the heat is much more supportable to one that stoops, than to one that stands upright, because the steams of sulphur gather in the hollow of the arch about a man's head, and are, therefore, much thicker and warmer in that part than at the bottom. The three lakes of Agnano, Avernus, and the Lucrin, have now nothing in them particular. The Monte Novo was thrown out by an eruption of fire that happened in the place where now the mountain stands. The Sulfatara is very surprising to one who has not seen Mount Vesuvio. But there is nothing about Naples, nor indeed in any part of Italy, which deserves our admiration so much as this mountain. I must confess the idea I had of it did not answer the real image of the place when I came to see it; I shall therefore give the description of it as it then lay.
This mountain1 stands at about six English miles' distance from Naples, though, by reason of its height, it seems much nearer to those that survey it from the town. In our way to it we passed by what was one of those rivers of burning matter, that ran from it in a late eruption. This looks at a distance like a new-ploughed land, but as you come near it you see nothing but a long heap of heavy disjointed clods lying one upon another. There are innumerable cavities and interstices among the several pieces, so that the surface is all broken and irregular. Sometimes a great fragment stands like a rock above the rest, sometimes the whole heap lies in a kind of channel, and in other places has nothing like banks to confine it, but rises four or five foot high in the open air, without spreading abroad on either side. This, I think, is a plain demonstration that these rivers were not, as they are usually represented, so many streams of running matter; for how could a liquid, that lay hardening by degrees, settle in such a furrowed uncompact surface? Were the river a confusion of never so many different bodies, if they had been all actually dissolved, they would at least have formed one continued crust, as we see the scorium of metals always gathers into a solid piece, let it be compounded of a thousand heterogeneous parts. I am apt to think therefore, that these huge,
The following description of Mount Vesuvio is surprisingly clear and graphical. One could scarce have a better idea of it from surveying it on the spot.
unwieldly lumps that now lie one upon another, as if thrown together by accident, remained in the melted matter rigid and unliquefied, floating in it like cakes of ice in a river, and that, as the fire and ferment gradually abated, they adjusted themselves together as well as their irregular figures would permit, and by this means fell into such an interrupted, disorderly heap, as we now find it. What was the melted matter lies at the bottom out of sight. After having quitted the side of this long heap, which was once a stream of fire, we came to the roots of the mountain, and had a very troublesome march to gain the top of it. It is covered on all sides with a kind of burnt earth, very dry, and crumbled into powder, as if it had been artificially sifted. It is very hot under the feet, and mixed with several burnt stones and cakes of cinders, which have been thrown out at different times. A man sinks almost a foot in the earth, and generally loses half a step by sliding backwards. When we had climbed this mountain, we discovered the top of it to be a wide, naked plain, smoking with sulphur in several places, and probably undermined with fire, for we concluded it to be hollow by the sound it made under our feet. In the midst of this plain stands a high hill in the shape of a sugar-loaf, so very steep that there would be no mounting or descending it, were not it made up of such a loose crumbled earth as have before described. The air of this place must be very much impregnated with saltpetre, as appears by the specks of it on the sides of the mountain, where one can scarce find a stone that has not the top white with it. After we had, with much ado, conquered this hill, we saw in the midst of it the present mouth of Vesuvio, which goes shelving down on all sides till above a hundred yards deep, as near as we could guess, and has about three or four hundred in the diameter, for it seems a perfect round. This vast hollow is generally filled with smoke, but, by the advantage of a wind that blew for us, we had a very clear and distinct sight of it. The sides appear all over stained with mixtures of white, green, red, and yellow, and have several rocks standing out of them that look like pure brimstone. The bottom was entirely covered, and though we looked very narrowly, we could see nothing like a hole in it; the smoke breaking through several imperceptible cracks in many places. The very middle was firm ground when we saw it, as we con
cluded from the stones we flung upon it, and I question not but one might then have crossed the bottom, and have gone up on the other side of it, with very little danger, unless from some accidental breath of wind. In the late eruptions this great hollow was like a vast caldron filled with glowing and melted matter, which, as it boiled over in any part, ran down the sides of the mountain, and made five such rivers as that before mentioned. In proportion as the heat slackened, this burning matter must have subsided within the bowels of the mountain, and as it sunk very leisurely, had time to cake together, and form the bottom which covers the mouth of that dreadful vault that lies underneath it. The next eruption, or earthquake, will probably break in pieces this false bottom, and quite change the present face of things.
This whole mountain, shaped like a sugar-loaf, has been made at several times by the prodigious quantity of earth and cinders, which have been flung up out of the mouth that lies in the midst of them, so that it increases in bulk at every eruption, the ashes still falling down the sides of it, like the sand in an hour-glass. A gentleman of Naples told me, that in his memory it had gained twenty foot in thickness, and I question not but in length of time it will cover the whole plain, and make one mountain with that on which it now
In those parts of the sea that are not far from the roots of this mountain, they find sometimes a very fragrant oil, which is sold dear, and makes a rich perfume. The surface of the sea is, for a little space, covered with its bubbles during the time that it rises, which they skim off into their boats, and afterwards set a separating in pots and jars. They say its sources never run but in a calm warm weather. The agitations of the water perhaps hinder them from discovering it at other times.
Among the natural curiosities of Naples, I cannot forbear mentioning their manner of furnishing the town with snow, which they here use instead of ice, because, as they say, it cools or congeals any liquor sooner. There is a great quantity of it consumed yearly, for they drink very few liquors, not so much as water, that have not lain in Fresco, and everybody, from the highest to the lowest, makes use of it; insomuch, that a scarcity of snow would raise a mutiny at Naples, as much as a dearth of corn or provisions in another