Oct. 9, 1S84] 



NA TURE 



565 



opens to view by looking over the verge of this crater 

 down into the precipitous abyss. The crater, with its 

 bottom covered with snow and the sides all whitened with 

 a glacial crust, suggests to the beholder a gigantic cauldron 

 hollowed out in marble. Enormous rocks, which have 

 tumbled down from the brim of the crater, look like 

 minute black specks against the whiteness of the bottom. 

 The composition of the lava is practically entirely 

 basaltic ; but reddish rocks of trachyte are strewn about 

 the circumference of the original crater, which shows that 

 sometimes trachytic eruptions have taken place here, as 

 in Askja in 1875. When the weather cleared, I had dis- 

 tinctly in view the greater part of OdctSahraun as well as 

 Dyngjufjoll proper, and all the lava currents which have 

 taken their course from the latter complex of volcanoes. 

 In a north-westerly direction from the above-described 

 volcano is another, lower, but quite as wide in circum- 

 ference, to which we gave the name of Kerlingar-Dyngja. 

 Having surveyed Uyngja, we returned the same way we 

 had come, and reached our tent at half-past two o'clock 

 the next morning. 



In a southerly direction from HerSubreiS there extends 

 a very considerable mountain range, 3400 feet high, which 

 is called Tfigl (Tails) ; it is separated from Her$ubrei<5 by 

 a narrow gate through which, once upon a time, a lava 

 current has found its way. Thus HerSubreiS is sur- 

 rounded by lava on all sides, though that mountain itself 

 is no volcano, but a pile of coarse palagonite breccia 

 interspersed with stray thin layers of basalt throughout 

 its lower parts. One of my excursions I directed to the 

 Togl. From the tops of these mountains an extensive 

 view opens southward over the sands along the course 

 of Jokulsa and the northern region of Vatnajokull. The 

 aspect of the country to the south of HerSubreiS is truly 

 forbidding, all covered with the yellow-gray scoriae from 

 the explosion of Askja in 1S75, generally one to two feet 

 in thickness, and no sign anywhere of vegetation. The 

 whole southern horizon exhibits the vast expanse of the 

 snow-white glacial bolsters of Vatnajokull, out of which, 

 in a northerly direction, rises the enormous complex of 

 volcanoes called Kverkfjoll. In some fiery convulsion this 

 mass of mountains has split from end to end, and through 

 the rent a glacier has found its way right down to the 

 level land below. To the west of this rent I observed in 

 the jokull a mass of craters, from one of which huge 

 clouds of white steam ascended into the air. Nothing is 

 known about the volcanic activity in this spot, no one 

 having ever visited those parts of Vatnajokull. On the 

 western side of Kverkfjoll the jokull is one flat ice plateau 

 all the way down to OdaSahraun, skirting into a number 

 of moving glaciers terminating in sands and extensive 

 moraines, from which flow innumerable affluents to 

 Jokulsa in Axarfjord. Towards the east, about the 

 approaches to Sandfell, the next highest mountain in Ice- 

 land (5800 feet), the jokull exhibits sharp-cut black vertical 

 walls, probably ledges of underlying basaltic belts ; but 

 further to the west the flatness of the jokull owes its 

 formation to the substratum being made up of pala- 

 gonite tufa, a softer and more easily ground material. 

 Our western view was determined by a part of OdaSa- 

 hraun, southern Dyngjufjoll, Askja, and the southern 

 parts of HerSubreiSarfjoll. At the southern termination 

 of Dyngja there rises a very peculiarly formed tufa "fell," 

 along the crest of which is to be observed a row of a 

 number of vertical tufa peaks, each from one to two 

 hundred feet high, so that the outline of the mountain 

 gives the impression of a gigantic hedgehog. 



Next day I set out on the examination of HerSubreiSar- 

 fjoll. Directing our course to the north-east, we ascended 

 on our way a mountain by the banks of Jokulsa called 

 Ferjufjall, near which, as the story goes, there was a ferry 

 in those olden times, when the bishops were in the habit 

 of taking that road over the northern skirts of OdaSa- 

 hraun, to which I have alluded already. In a north- 



westerly direction from this place excessively ancient 

 lavas come to view, which are clearly older even than the 

 Glacial period, exhibiting everywhere large and unmis- 

 takable signs of glacial abrasions. In this excursion we 

 came upon a row of those beacons which by general 

 custom in Iceland are erected to point out where roads 

 run through wildernesses. Most of these beacons were 

 but cumuli of stones ; one, however, we found still 

 standing, covered with moss and lichens. This we knew 

 now must be the eastern end of the long-lost road, an 

 assumption which subsequent discovery corroborated. As 

 we approached nearer to Htr$ubrei<5arfj611 we came upon 

 a series of craters surrounded by a recent lava, and so 

 rough that no horse might cross it, almost impassable 

 even for a traveller on foot. Leaving our ponies behind, 

 we made our way across this lava, however, as best we 

 could, and reached the highest crest of the mountains 

 shortly before sunset, and enjoyed from it an extensive 

 view. All about these mountains, which are composed of 

 palagonite breccia, there is a number of ridges observable, 

 with small dales and narrow dips scooped out between 

 them, all, however, totally barren of vegetation. About 

 the central portion this range sinks down into low necks 

 honeycombed with many large craters, from which floods 

 of lava have spread over the surrounding country on both 

 sides, east and west, covering an area of some tens of 

 square miles. Having completed my survey of this 

 region, we returned and joined our ponies shortly after 

 midnight, all scratched and lacerated from the lava, with 

 our shoes and stockings in shreds. 



Th. Thoroddsen 

 ReykjahlfS, near Myvatn, August 4 

 {To be continued.) 



THE CONNECTION BETWEEN CHINESE 

 MUSIC, WEIGHTS, AND MEASURES 



CHINESE music can now be heard by all who desire 

 to hear it at the Health Exhibition, and more may 

 be learned on the subject from the pamphlet published 

 by the Commissioners for the Chinese department. A 

 curious account of the common origin of Chinese weights, 

 measures, and musical notes is contained in a paper read 

 some years ago before the German Asiatic Society of 

 Japan by Dr. Wagener. The story is based on native 

 legends, and is also to be found among the Jesuit 

 " Memoires concernant les Chinois." Dr. Wagener says 

 there is not the slightest doubt that the Chinese system 

 of weights and measures is more than 4600 years old ; 

 and it is a highly remarkable circumstance that, quite 

 irrespective of the fact that it is more scientific and 

 exact, it possesses all the advantages for which the 

 French metrical system is so much praised. In the first 

 place, it starts from a basis supplied by Nature ; secondly, 

 the decimal arrangement is almost consistently employed 

 throughout ; thirdly, linear and dry measure proceed 

 directly from the same unit as the measure of weight ; 

 and lastly, what the metrical system does not do, it 

 regulates in the simplest manner the relations of musical 

 notes, which latter form the starting-point for the whole 

 system of weights and measures. The following account 

 of the origin of this system (says Dr. Wagener) contains 

 fact and fancy mingled, but it is easy to distinguish 

 between them. In the reign of the Emperor Hoang-ti, 

 who ruled over China in the twenty-seventh century 

 before Christ, the scholar Lyng-lun was commissioned to 

 complete the musical system which had been discovered 

 250 years earlier, and particularly to lay down fixed rules 

 for making musical instruments. Naturally he had to 

 commence with the bamboo, which had already been long 

 used to give the note for other instruments. He there- 

 fore betook himself to the province of Siyung in North- 

 Western China, where, on the northern slope of a range of 



