This section is from the book "Askja: Iceland's Largest Volcano", by W. G. Lock. Also available from Amazon: Askja: Iceland's Largest Volcano.
Having stated that Mr. Watts' account of the Dyngjufjoll and Askja is in some very important particulars incorrect, it will perhaps be as well, as their description in his paper read before the Eoyal Geographical Society does not quite occupy the whole of a page of ' The Proceedings of the Society,' to quote it, that those of my readers who are not in possession of the ' Proceedings' for 1876, may see what that gentleman had to say about the volcano, and be in a position to judge when they have perused this little work whether I am justified in my comment.
' I " cached" two days' provisions and proceeded to the Dyngjufjoll. I found these mountains to consist of a series of semi-detached sections, some of which had broken out in ancient times, and by their insignificant (!) lava-streams had helped to swell the widely-extending lava desert of the Odadahraun.
' These sections of mountains described a heart-shaped form upon the south, enclosing the Askja. This is a three-cornered piece of elevated land 4,000 feet high, about six miles long and three or four broad; it is easily reached by a glen upon the north-east side of the Dyngjufjoll. The principal crater, which erupted this year, is situated in the south corner of the Askja..
4 The crater is enclosed upon the eastern and western sides by mountains rising in some instances 1,000 feet above the Askja plain; they appear shorn of their inner faces by the violence of the eruption, forming perpendicular cliffs of great height.'
I cannot pass this statement without observing that this is the case only on the eastern side of what Mr. Watts terms the ' crater' (the abyss formed by the subsidence, now the bed of a thermal lake), as the encircling mountain-wall, save to the east and south, is four and a half miles distant, the plain of Askja lying between. (See Map.) To continue :
' These cliff's are rapidly falling in. avalanches of stone occurring at frequent intervals, and had formed in two places steep slopes of pumice and debris, which it is possible to descend; all access to the floor of the crater is prevented, however, by an interior rim of the precipice immediately at the base of the heights.'
I here omit a paragraph eulogising the view over Ashja, as it is not descriptive.
' This volcano, which, perhaps, we may be allowed to call the Oskjagja (the chasm of the oval casket),* does not appear to have produced anything but pumice, mud, and water, copious floods of the latter having evidently flowed from its crater. It is curious to remark that although this volcano has ejected water, it is neither a glacial nor a snow-capped mountain, and it is situated more than 100 miles from the sea.'
* I regret to have to add that the poetical name ' cliasm of the oval casket,' which Mr. Watts here asks to be allowed to call the volcano, is unknown outside of his paper and book, Oskjugjd (Oshju-genitive of Ashja, gjd-a rift) signifying Basket-rift. It will be noticed, moreover, that the word is spelt incorrectly by Mr. Watts.
I must again pause for a moment to observe that even a glance at the map accompanying Mr. Watts' paper would have prevented such a misstatement as that Ashja 'is situated more than 100 miles from the sea,' it being, as before observed, and as will be seen by the map of Iceland herewith, almost equidistant from the north, south, and east coasts, the distance in an air-line being about sixty miles. It is also worthy of notice that Mr. Watts speaks of the mountain here in the singular, as being ' neither a glacial nor a snow-capped mountain,' not as ' sections of mountains,' and he is quite right in doing so, though hardly consistent; but he is quite wrong, as we shall presently see, in asserting that the mountain is neither glacial nor snow-capped; no doubt he meant to show that the floor of Ashja was bare of snow and ice. He concludes his brief description as follows:
' Leaving the volcano of Askja behind us and proceeding in a westerly direction, we perceived that the lava from the Od;ida-hraun had entered the Askja upon its most western side, having run for a considerable distance up hill. Upon descending the Dyngjufjoll to the west, a broad plaiu, baiTen and black with sand and lava, opened before us; this was the Odiida-hraun.'
I should fancy that the Fellows of the Royal Geographical Society were about as wise subsequent as they were prior to the reading and publication of the above, as to the exact situation, magnitude, and appearance of Askja. It most certainly does not convey an impression to one's mind of a vast, almost circular crater over seventeen miles in circumference, lying at a depth of 800 feet at the least, within a mountain, its mountainous periphery broken by gaps to the present level of the floor of the crater in two places only; of a mountain that had been built up by the deposit of innumerable lava-flows around and above a volcanic-vent to the height of 2,300 feet above the plain of the Oddffahraun, equal to 3,800 feet above sea level, and subsequently heightened by the upheaval of the immense masses of these lava-deposits, and of the substrata that now form Askja's periphery, the outer circumference of which, at an altitude of 3,500 feet, cannot be less than twenty-four miles. The altitude given by Mr. Watts of the lava-covered floor of Askja, 4,000 feet, is correct within a hundred feet or so, as also is the height of the encircling mountain wall, 'rising in some instances 1,000 feet above the Askja plain;' in fact it varies in height from 800 to 1,500. I have never visited the western gap, through which Mr. Watts says the lava has entered from the Oddffahraun, therefore I cannot say whether he is correct or not, but I have examined the eastern one, and there, lava that has issued in Askja has streamed out, not entered in; and, as the superficial lava in that crater lies at the least 2,300 feet above the level of the Oddffahraun, it is quite certain, if Mr. Watts is right, that the lava which entered the western gap had ' run for a considerable distance up hill.'