At this particular point it is bordered by a rather fertile stretch of ground, where a few sheep managed to sustain a miserable existence on cinders and salix, though further to the north and east there are excellent pastures. The lava stream was basaltic, and presented the usual chaos of black crags, waves, and fanciful shapes, blisters, and heaps of clinker. It was intensely black, and still hot; thin, pungent choking fumes being emitted in all directions, while from various places puffs of steam were constantly bursting out. This stream, or rather, these two streams, which have since joined one another, I find have flowed from a long fissure in the plain, the course of which was marked by a line of conical mounds thrown up by the eruptions in the late spring; of these a fuller description will be found upon another page, and an account of the previous eruption in the Appendix.
We climbed a few hundred yards over the lava stream, but could not reach the mounds from which the lava had flowed, on account of the deleterious fumes exhaled from them. The fissures were lined with various sublimations, to the thickness in some places of half-an-inch. Amongst them chloride of ammonia was very prominent, but this was in a state of rapid deliquescence. It might have paid to collect it, for the quantity was considerable.
We next turned more than a mile out of our course, to a part where Thorlákur expected to find some water, for we were all very thirsty. Our road, however, was over old and viscous lava for some distance, and we came upon some coarse hillocky grass land, in a line north of the lava stream. Here we encountered a variety of fissures which had been formed by the earthquake, several of which, Thorlákur informed me, had cast out sand, stones, and a little lava. We found only dry pits at the place where Thorlákur had expected water, so nothing remained but to strike westward for Reykjahlíð. No doubt the various cracks and fissures so recently formed in the plain accounted for the absence of water.
The new lava obliges a traveller from Grímstaðir to Reykjahlíð to go three miles out of his way. We here crossed a depression of about thirty feet, extending over several square miles, caused by the late volcanic disturbances. In the vicinity of this depression the ground was upheaved and much fissured. Thorlákur informed me that the depression was formed shortly after the first eruption in the Mývatn Orœfí in the preceding spring. We were, however, soon amongst the hills of Mývatn, where we obtained some water, and before long ascended the Námufjall, whose dirty yellow, red and brown sides, had in some places the appearance of washed-out posters. Here the smell was filthy. In this locality the treasures of the Northern Sulphur Mining Company are situated, but as I was thinking more about my supper than the hidden wealth of the hills over which we were riding, I will say more about them presently.
A wadi near the summit which divides the Námufjall upon the south from the Dalfjall upon the west, brought us to the western side of the sulphur hills, where we first caught sight of the Lake of Mývatn, or Midge-water, upon the north end of which Reykjahlíð is situated. Lake Mývatn is seen to the best advantage at a distance, but it cannot lay claim to great beauty of appearance, although certainly both remarkable and interesting. Surrounded as it is with volcanic mountains, and rugged lava streams stretching along its shores, studded with misshapen little islands, it presents an eccentric and striking aspect. A short ride past spluttering and steaming solfataras brought us to the farm of Reykjahlíð, where we were hospitably received by the bóndi Pètur Jónsson, who was expecting our arrival.
Reykjahlíð is of the average better class of byre. The farm is a good one, and has been in the possession of the same family for 600 years. I was glad to find Paul and the rest of my belongings awaiting us, and anything but displeased to receive the information that an Englishman occupied the guest chamber. My compatriot I found to be Mr. G. Fitzroy Cole, who was making a survey of the neighbourhood for the Company purposing to work these northern sulphur mines. I also heard that a sulphur prospecting party, under the guidance of the well-known Captain Burton, had only just left for Húsavík, upon the sea coast. The guest chamber being thus occupied, I shared another room with Paul and Thorlákur, and in the morning I had the pleasure of making Mr. Cole’s acquaintance, sharing the guest room with him, and likewise a magnificent salmon.
The two days following I rested, as the weather was so unfavourable. I also paid off all my men excepting Paul and Olgi, and sent them home to the south. Mr. Cole in the meantime left, so I proceeded to investigate the sulphur mines for myself. These I found to be situated in the Námufjall, upon the eastern side of the Lake of Mývatn, and these collectively are designated the Hlíðar-Námur; they consist of a series of solfataras, which occur not only upon the Námufjall itself, but extend a considerable distance upon either base of the mountains. The Námufjall is composed of palagonitic agglomerate and lava, the solfataras being simply pools of calcareo-siliceous mud, formed by the decomposition of the lava and agglomerate. Upon the surface of these pools the sulphur sublimates in crusts varying from half-an-inch to several feet in thickness. The phenomena of solfataras are so well known that it is needless for me to dilate upon them in the abstract. However, I first examined the west side of the Námufjall, where I found both active and latent fumeroles, the former spluttering and fizzing, and tranquilly steaming, the latter in the form of cold accumulations of sulphur, siliceous clay and gypseous earth. I was able to follow the tracks of the sulphur exploring party, who had preceded me. They had dug into the sulphur crust upon the surface of the solfataras, and in some places had excavated the calcareo-siliceous clay, which hardens into a species of sinter. This clay likewise contains a percentage of sulphur; at all events the specimens I obtained varied from 5 to 40 per cent. In many places I found crusts of sulphur covered over with light débris, which a little digging showed to extend for a considerable distance. Roughly estimating it by stepping the length and breadth of the various conspicuous sulphur patches, and lumping the smaller ones together, gave about twenty sulphur-covered spots of twenty square yards, upon which the crust of pure sulphur averaged probably half a foot in thickness. On ascending the Námufjall by a deep gulley worn by the rain in the side of the mountain, we found this gulley to be cut through several feet of a friable arenaceous agglomerate, formed by atmospheric action on the disintegrated constituents of the rocks composing the Námufjall. Passing various patches of steaming sulphur, we reached the summit, where we found several solfataras which bear perhaps the thickest deposits of sulphur, though, in the aggregate I should hardly think they extend over so large an area as those upon the western side of the mountain. This mountain is capped by several castellated masses of basaltic lava, much weather-worn and decomposed by the acid vapours evolved from the surrounding solfataras, which upon the eastern slope are decidedly the most extensive to be met with, and I imagine they contain more pure sulphur than either the summit or the western side. Of course when speaking of the relative amount of sulphur, I allude to the exposed crusts, and there must be a great deal more sulphur than appears upon the surface.
Upon the east base were circular pools of bluish boiling slush, which emitted a fœtid smell somewhat resembling the effluvia which so disgusted us at the Öskjugjá. These pools boil with great but intermittent violence, sometimes splashing the scalding mud to the distance of four or five feet. They have surrounded themselves with walls of hardened mud a few feet in height, and from a breach in two of these walls I should imagine that these springs were occasionally subject to paroxysms of extraordinary violence. While approaching the most northern of these slush cauldrons, the earth on which I was walking gave way, and I slipped into a fissure up to my armpits; a violent burst of steam from beneath me was the immediate result, and I was glad to be extricated from this unenviable position by my companion Olgi. It was indeed fortunate the fissure was not filled with boiling slush, or I might have been scalded even more severely than was my travelling companion, the Rev. J. W——, in 1874, in the solfataras of Krísuvík, in the south of Iceland. This fissure had probably been formed by the earthquakes in the spring, and had at one time been filled with slush, which had hardened on the surface, and afterwards flowed away through some other channel, leaving a treacherous pitfall for any unlucky tourist who, like myself, should have a fancy to closely examine these slush pools.
On returning to the west side of the mountain, and on my way to Reykjahlíð, I took the liberty of scraping off all the sulphur from a small solfatara, which I piled in a heap by the side of it; for the grand question for the Sulphur Company to consider, to my mind, appears to be—how long does this sulphur take to accumulate? I trust Mr. Locke, the owner of these mines, will forgive me the trespass; but in a year’s time he will be able to form some idea of the rate of accumulation. I shall feel curious to know how soon the sulphur will again accumulate.