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THE HOT SPRINGS of ReikHOLT. rock, in which water also boils

From the same.

The hot springs in the valley of Reikholt, or Reikiadal, though not the most magnificent, are not the least curious among the numerous phenomena of this sort that are found in Iceland. Some of them, indeed, excite a greater degree of interest than the Geyser, though they possess none of the terrible grandeur of that celebrated fountain; and are well calculated to exercise the ingenuity of natural philosophers. On entering the valley we saw numerous columns of vapour ascending from different parts of it. The first springs we visited, issued from a number of apertures in a sort of platform of rock, covered by a thin coating of calcareous incrustations. I could not procure any good specimens, but from those we broke off, the rock appeared to be greenstone. From several of the apertures the water rose with great force and was thrown two or three feet into the air. On plunging the thermometer into such of them as we could approach with safety, we found that it stood at 212°.

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A little further up the valley, there is a rock in the middle of the river, about ten feet high, twelve yards long, and six or eight feet in breadth. From the highest part of this rock a jet of boiling water proceeded with violence. The water was dashed up to the height of several feet. Near the middle, and not more than two feet from the edge of the rock, there is a hole, about two feet in diameter, full of water boiling strongly. There is a third hole near the other end of the

briskly. At the time we saw these springs, there happened to be less water in the river than usual, and a bank of gravel was left dry a little higher up than the rock. From this bank a considerable quantity of boiling water issued.

About two miles further up the valley on the opposite side of the river, whose windings rendered it necessary for us to cross it several times, are the church of Reikholt, and the minister's house. We went thither for the purpose of examining a bath which was built nearly 600 years ago by the celebrated Snorro Sturleson. The bath is a circular bason, constructed of stones, apparently without any cement, but nicely fitted together. It is about fourteen feet in diameter, and altogether about six feet deep, the water being allowed to fill it to the depth of about four feet. The hot water is brought from a spring about 100 yards distant, by means of a covered conduit, which has been somewhat injured by an earthquake. We were told that cold water had been brought to it, so that, by mixing the hot and cold together, any desired temperature might be obtained. All round the inside, a little way under the surface of the water, was a row of projecting stones, placed ap parently to serve the purpose of steps. Steps were constructed as an entrance to the bath, close to the orifice by which the hot water entered. At present it is not much used, and the bottom is covered with vegetable matter and soil.

In the absence of the minister we were politely received by his

wife, who gave us some excellent cream; a good proof of the quality of the pastures of this valley. Proceeding down the valley on the side opposite to that on which we entered it, we came to a group of cottages, situated close to some hot springs. In the water of one of them we saw some pots, containing milk and curds. There is a sort of natural dome, several feet in diameter, formed over part of this spring of clay and stones. It intermits at short, and pretty regular intervals. Having sat down near an orifice in the dome from which steam was rushing, we oberved that the noise suddenly ceased, and the water, when it was visible, sunk down amongst the stones in its channel, leaving them dry. After a short interval the noise recommenced, steam rushed forth, and boiling water followed. We observed many repetitions of this phenomenon; and the intervals were scarcely two minutes. It may be easily explained in the same manner as that of ordinary intermittent springs, connecting such an apparatus as is supposed to belong to them, with one in which steam may be brought into action in order to force the water upwards. Upon part of the mound or dome mentioned above, and extending a little way beyond, a hut was constructed the entrance to which was by a long, narrow, and low passage. The heat of the earth occasioned by the hot water was here confined, so that the temperature of the air was 73°. No use was made of this hut except for the drying of clothes. It is singular that the people have not contrived the means of heating

their apartments by the hot springs that are steady in their operations. One would think, that the great scarcity of fuel and the difficulty of procuring it, would have suggested this long ago. The fear of danger does not exist, for the habitations are close to the springs; and near the place where boiling water is thrown out with the most terrible violence, and which will afterwards be de scribed, the natives quietly repose. Their not having taken advantage of this natural source of comfort, must proceed from that want of enterprise, which is so conspicuous in the character of the Icelanders.

About a mile further down, at the foot of the valley, is the Tunga-hver, an assemblage of springs the most extraordinary, perhaps, in the whole world. A rock (wacke?) rises from the bog, about twenty feet, and is about fifty yards in length, the breadth not being considerable. This seems formerly to have been a hillock, one side of which remains covered with grass while the other has been worn away, or perhaps destroyed at the time when the hot water burst forth. Along the face of the rock are arranged no fewer than sixteen springs, all of them boiling furiously, and some of them throwing the water to a considerable height. One of them however deserves particular notice. On approaching this place we observed a high jet of water, near one extremity of the rock. Suddenly thisjet disappeared, and another, thicker, but not so high rose within a very short distance of it. At first we supposed that a piece of the rock had given way,

and that the water had at that moment found a more convenient passage. Having left our horses, we went directly to the place where this had apparently happened; but we had scarcely reached the spot, when this new jet disappeared, and the one we had seen before was renewed. We observed that there were two irregular holes in the rock within a yard of each other; and while from one, a jet proceeded to the height of twelve or fourteen feet, the other was full of boiling water. We had scarcely made this observation, when the first jet began to subside, and the water in the other hole to rise; and as soon as the first had entirely sunk down, the other attained its greatest height, which was about five feet. In this extraordinary manner, these two jets played alternately. The smallest and highest jet continued about four minutes and a half, and the other about three minutes. We remained admiring this very remarkable phænomenon for a considerable time, during which we saw many alternations of the jets, which happened regularly at the intervals already mentioned.

I have taken the liberty to give a name to this spring, and to call it, the Alternating Geyser.'

These springs have been formerly observed, though the singularity of the alternations does not seem to have been attended to as any thing remarkable. Olafson and Paulson mention, that the jets appear and disappear successively in the second, third, and fourth openings. We observed no cessation in any of the springs VOL. LIII.

but in the two under consideration.

To form a theory of this regular alternation is no easy matter; and it seems to require a kind of mechanism very different from the simple apparatus usually employed by nature in ordinary intermittent or spouting springs. The prime mover in this case is evidently steam, an agent sufficiently powerful for the phænomena. The two orifices are manifestly connected; for, as the one jet sinks towards the surface, the other rises; and this in a regular and uniform manner. I observed once, that when one of the jets was sinking, and the other beginning to rise, the first rose again a little before it had quite sunk down; and when this happened, the other ceased to make any efforts to rise, and returned to its former state, till the first again sunk, when the second rose and played as usual. This communication must be formed in such a manner, that it is never complete, but alternately interrupted, first on one side, and then on another. To effect this without the intervention of valves seems to be impossible; and yet it is difficult to conceive the natural formation of a set of permanent valves; so that this fountain becomes one of the greatest curiosities ever presented by nature, even though, in attempting to explain the appearances it exhibits, we take every advantage that machinery can give us. If it is occasioned by natural valves, these must be of very durable materials, in order to withstand continual agitation and consequent

attrition.

2 K

ACCOUNT OF THE GEYSERS. By water, very much resembling the

Sir G. Mackenzie.

We were occupied this morning in examining the environs of the Geysers: and at every step received some new gratification. Following the channel which has been formed by the water escaping from the great bason during the eruptions, we found some beautiful and delicate petrifactions. The leaves of birch and willow were seen converted into white stone, and in the most perfect state of preservation; every minute fibre being entire. Grass and rushes were in the same state, and also masses of peat. In order to preserve specimens so rare and elegant, we brought away large masses, and broke them up after our return to Britain; by which means we have formed very rich collections; though many fine specimens were destroyed in carrying them to Reikiavik. On the outside of the mount of the Geyser, the depositions, owing to the splashing of the water, are rough, and have been justly compared to the heads of cauliflowers. They are of a yellowish brown colour, and are arranged round the mount somewhat like a circular flight of steps. The inside of the bason is comparatively smooth; and the matter forming it is more compact and dense than the exterior crust; and when polished, is not devoid of beauty, being of a grey colour, mottled with black and white spots and streaks. The white incrustation formed by the water of the beautiful cavity before described, had taken a very curious form at the edge of the

capital of a Gothic column. We were so rapacious here, that I believe we did not leave a single specimen which we could reach; and even scalded our fingers in our eagerness to obtain them. We found the process of petrifaction in all its stages; and procured some specimens in which the grass was yet alive and fresh, while the deposition of the silicious matter was going on around it. These were found in places at a little distance from the cavity, where the water running from it had become cold.

About a hundred yards from the Great Geyser towards the north, in the cleft where the disruption already mentioned had taken place, and which has prôbably been formed by an earthquake, are banks of clay, in which there are several small basons full of boiling mud. The mud is thin, and tastes strongly of sulphate of alumina, of which we observed many films attached to the clay, which seems to have been forced up from below, through fissures in the ancient incrustations. The clay contains also iron pyrites; the decomposition of which has given it very rich colours. Almost directly above this place, under the rock at the top of the hill, are several orifices, from which steam rushes; and there are some slight appearances of sulphur. Almost the whole of this side of the hill is composed of incrustationsand clay.

The depositions of the present and former springs are visible to a great extent, about half a mile in every direction; and, from their great thickness in many places, it

is probable that they are spread under the surface now covered" with grass and water, to a very considerable distance. About half a mile up the rivulet, in the direction of Haukardal, where there is a church, another hot spring appears, which deposits silicious matter. From thence we obtained one of the most curious specimens we collected; it almost perfectly resembles opal. I mention the situation of this spring to show the probability that the extent of the matter, which may for ages have been collecting, is very great; and its depth, from what is seen in the cleft near the Geyser, where it is visible to the thickness of ten or twelve feet, is probably also very considerable.

It is somewhat curious, that no particular notice has been taken by the early Icelandic authors of this, the most remarkable spot in all the island. Though hot springs are without number, and occur in every part of the country, and may be regarded with indifference, yet the Geysers must have been remarkable at all times; for the extent of the old incrustations shows them to have been deposited by springs of no ordinary dimensions. They are, it is true, on the verge of that vast district of uninhabited and desolate country which forms the interior of Iceland. In looking around as we approached the place, nothing was seen but rugged mountains, far extended swamps, and frightful Jokuls rearing their frozen summits to the sky. Nothing in this direction seemed to invite the curiosity or enterprize of people already accustomed to the horrors of volcanic eruptions, and fully aware that their only

At

sure subsistence was to be derived from the sea. The indifferent and casual manner in which the Geysers are mentioned by Arngrim Jonas, shows this want of curiosity even among the learned of the Icelanders. He speaks of some great springs near Haukardal, to the north of Skalholt, which he had never himself seen, but of which he had heard that they deposited incrustations, and changed vegetable matter into stone. the present day, the number of the natives who have visited these springs is comparatively, very small; and, by those who live near them, their extraordinary operations constantly going on,. are regarded with the same eye as the most common and indifferent appearances of nature. Towards the north-east, and east, the country is low; the only elevated ground that appears towards the south-east being the summits of Hekla, and Eyafialla Jokul. Several Jokuls break the view towards the north; and we remarked one mountain which had several rugged and peaked summits soaring to a great elevation.

However strongly the feelings excited by the productions of the springs, and by the appearance of the surrounding country, were impressed upon us, we often turned anxiously towards the Geysers, longing for a repetition of their wonderful operations. To them all our wishes and hopes were directed; and we felt as if our eyes could never tire of beholding, nor our minds weary of contemplating them. The descriptions we had read, and the ideas we had formed of their grandeur, were all lost in the amazement excited on their

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