Oct. 29, 1874] 



NATURE 



523 



4 A ^,1. Aug'.st 29, subicnMiiCTri liimblitigs were folio'.vfd 

 by two shocks, when a formidable column of black smoke 

 and flaming materials rushed tip into the air, and, carried 

 by the wind, fell at great distances, in the form of small 

 scoria; and sand. Numerous other columns succeeded, 

 with roaring', rumbling noises, lasting for seven hours with 

 great intensity, dying away towards night. The noises 

 ceased on the 30th of August, and vapour and smoke 

 alone rose from the crater and along the line of dis- 

 turbance. 



When the volcanic tremors were most intense, at 

 4 A.M. 29th August, a fissure appeared on the north side 

 of the great central crater, extending for five kilometers, 

 with an axis ranning E. by S^ N. The centre of the 

 impellant force was at an elevation of 2,450 metres, be- 

 tween two mountains of lava known as Fraff/Za /"//and 

 Monte Grigio, where the rent widened to its maximum 

 width of fifty to sixty metres, whence it narrows very 

 steadily towards the base, terminating after a course of 

 three kilometres. And at this altitude, where the greatest 

 thrust was manifested, may be noticed the formation 

 of a new mountain, or crater, with an elliptical contour, 

 coinciding with the fissure in the direction of the axis. 

 It has a diameter of about 100 metres, and covers a 

 superficial area of about 117,734 square metres. This 

 crater, now appearing as a new mountain, is formed of 

 dolerilic lava and a pre-historic grey Labradorite, torn 

 from the surface by the black lava of this eruption, in 

 which they are enveloped. There are thus mingled two 

 lavas of the most distant epochs in the history of Etna, 

 the older forming the framework of the mountain. The 

 crater shows internally the usual funnel shape ; and near 

 its base, over a width of fifty to sixty metres, there are 

 ten eruptive mouths, open wide, which succeed each other 

 like button-holes ; — those nearest the crater are abysses 

 twenty-five to thirty metres in diameter along the line of 

 the fissure. There are also two other groups of small 

 cones, in which the diameter of the mouths is not more 

 than from one to three metres — eight in the second 

 group, and four in the third ; so that within a distance of 

 half a kilometre from the crater there arc twenty-two 

 minor cones in linear extension. The crack is now con- 

 tinued down a declivity formed by the lava current of 

 1614, which slopes to the north at an angle of 13" or 14". 

 Although the rent traverses this lava, there are no more 

 small cones for a distance of 600 metres, when a fourth 

 group of five mouths, each two to three metres wide, is 

 found at an altitude of 2,170 metres; these latter have 

 poured out a ton-cnt of lava descending in a stream 150 

 metres long, 60 metres wide, and two metres thick. A 

 little low-er, at a height of 2,150 metres, is a fifth group of 

 three mouths, more active than the others, but situated 

 like the last group on the great lava stream of 1614. 

 The torrent of lava hurled from these mouths is 400 me- 

 tres long, So wide, and two metres thick, and forms two 

 short bifurcations. Finally, near the end of the crack, at 

 an altitude of 2,030 metres, a si.xth and last group of five 

 mouths is formed, which have ejected large quantities of 

 cinder and scoria:. They are situated about twelve kilo- 

 n-.etres from the old crater of I\Iojo, towards which this 

 great crack runs down the side of Etna from its central 

 crater. Besides this principal rent there are an infinite 

 number of smaller clefts, breaking up the soil and radi- 

 ating from the centres, of great dynamic activity. In a 

 few hours the new mountain and its system of about 

 thirty-five subordinate cones were thrown up, and thus 

 there was brought to the surface a total quantity of about 

 1,351,000 cubic metres of volcanic materials. 



The mingling of the old and new lavas will form the 

 subject of a subsequent memoir. The recent lava, like 

 all modern lavas, is augitic, black, magnetic, and has a 

 metallic lustre. Its specific gravity is 2'3636 at a tempe- 

 rature of 25° Cent. The superficial temperature of the 

 lava was 70°, while at a depth of half a metre it was go°. 



aiid a slill higher temperature was recorded where fume- 

 roles were active. 



From the remarkably short duration of the eruption. 

 Prof Silvestri anticipates a more powerful outburst to 

 come, which will be manifested along the rent in making 

 which the present internal explosion has spent its force. 



Concurrently with this disturbance the whole of volcanic 

 Italy has been affected. The island of Volcano, after a 

 century of quiescence, discharged cinders and flaming 

 materials from its vast crater for nine months previous to 

 the eruptive phenomena of Etna in the autumn of i S73. 

 The eruption of Volcano continued decreasing in intensity 

 through July 1874, and traces of it are still continually 

 seen. Stromboli last June made a rare eruption, sending 

 out small stones with great energy in place of its charac- 

 teristic feeble incessant explosions. 



Vesuvius has not been unsympathetic, and discharged 

 an unusual volume of dense vapour at the end of August 

 contemporaneously with the eruption of Etna. 



THE SECOND AUSTRO-HUNGARIAN EXPE- 

 DITION TO THE NORTH POLE, UNDER 

 WEYPRECHT AND PAYER, 1 87 2— 74. 



C\^ the return of the Austrian North Polar Expe- 

 ^^ dition we gave in Nature, vol. x. p. 439, an out- 

 line of the discoveries made. From the original memoirs 

 on the achievements of the voyage, by Dr. A. Petermann, 

 Dr. Joseph Chavanne, and Dr. v. Littrow, which have 

 been kindly forwarded to us by the first-named, along 

 with the map, we are able to give still further details. 



No general with his victorious army returning from 

 battle could have been welcomed with greater enthu- 

 siasm and cordiality than this little band of twenty- 

 two men. For though they only coine home from 

 a North Polar expedition, people instinctively feel that 

 the accomplishment of the Tegc///io/'s voyage is a 

 heroic deed. To gain a battle, hetacombs of precious 

 human lives must be sacrificed ; here all came safely 

 back. A battle does not demand greater endurance and 

 courage, for the battle of the Tegettliof lasted two years. 

 We think of the times of Columbus and Vasco da 

 Gama, of their discoveries and return to Palos and 

 Lisbon. It is true the Austrian expedition did not find 

 an America or an India ; but Columbus, and other great 

 discoverers, did not really discover more than Weyprecht 

 and Payei-. Before Columbus traversed it, men believed 

 that the western ocean was not navigable, and similar 

 ideas prevailed with more reason concerning the sea just 

 explored. One of the first describers of polar regions, 

 Scoresby, had, in the year 1S20, in his famous work, 

 drawn a line over the whole sea from Bear Island, in 

 744^ N. lat., to Novaya Zemlya, and said, with con- 

 fidence, " Here is' the icy barrier where navigation must 

 end ; " and the unknown regions beyond this line were 

 regarded by mariners with pious dread. The Austrian 

 expedition has torn away the veil up to 83° N. lat., and 

 has narrowed the undiscovered parts of the earth by a 

 space of S° to the north. 



They had to stay at Novaya Zemlya for four weeks, and 

 work their way out of thick ice for at least 240 geo- 

 graphical miles before reaching Cape Nassau, which w-as 

 the starting-point of the expedition. They then encoun- 

 tered the most terrific dangers which can befall a polar 

 expedition, for they were hemmed in by art ice floe, and 

 shut up for fourteen months in pack ice, and driven about 

 in the Siberian icy ocean. Eventually a tolerably safe 

 place in the open ice was found for the second wintering, 

 when the crew heroically divided themselves, the better 

 to explore the land they had discovered. 



The comrades of the Ti-gctlhofhsMe. shown themselves 

 worthy to take rank with their prototypes, Ross, Parry, 



