10 GEOLOGICAL MEMOIRS. 



the recent earthquake. The Visp Valley is one of many descending 

 from the crest of the Yalais Alps (the Monte Rosa group) to the 

 Valley of the Upper Rhone. It consists entirely of crystalline, with- 

 out any trace of volcanic rocks. 



The subterranean commotions, so frequent in these parts during 

 the summer of 1855, extended their destructive effects as far as Sion 

 (Sitten) in the Rhone Valley ; their greatest activity, however, was 

 concentrated about Vispbech (Viege), at the entrance of the valley, 

 Stalden, and St. Nicholas ; so that the centre of the earthquake-action 

 may be supposed to have existed between these three localities. 



Nearly all stone-buildings were more or less damaged or destroyed, 

 and most of the churches were so much injured by fissures as to 

 necessitate their being pulled down. The rocks also exhibit recent 

 crevices from 3 to 6 inches wide. Everywhere numerous new springs 

 of water have made their way to the surface, whilst formerly existing 

 springs have disappeared. 



Nearly all the devastation suffered by buildings is the effect of 

 a single strong commotion, which took place on July 25, 1855, 

 before one o'clock p.m. The subsequent movements had but sub- 

 ordinate effects, although they had not ceased in September, and 

 occurred at intervals as late as October. The line of greatest energy 

 extends from N.N.W. to S.S.E., for a distance of six hours (about 

 14 English miles). The earthquake of July 25 was felt through the 

 whole of Switzerland, the Savoy Alps, Lombardy, part of France, 

 Baden, Wirtemberg, Bavaria, and the Hessian territories. 



[Count M.] 



' JoHNSTONiTE/rom Transylvania. 



[Proceed. Imp. Geol. Instit. Vienna, November 13, 1855.] 



Baron Czoerning lately presented to the Museum of the Imperial 

 Geological Institute of Vienna some specimens of a mineral, disco- 

 vered in M. G. Hoffmann's lead-mines of Neu-Sinka, near Fogaras, 

 in Transylvania, to which the discoverer had given the name of 

 " Sinkanite." This mineral is a mechanical mixture of galena, an- 

 glesite, and sulphur. In one of these specimens, white compact 

 anglesite (sulphate of lead) traverses, in the shape of veins, a dark- 

 grey compound of sulphur and galena, being itself intersected with 

 delicate fissures filled with sulphur. This specimen shows evidently 

 the mode in which decomposition is gradually proceeding ; the sul- 

 phuret of lead disappearing, and sulphate of lead with sulphur re- 

 maining as a residuum. 



The mineral substance in question was first found at Dufton and 

 described by Mr. Johnston. Subsequently M. Haidinger named it 

 *' Johnstonite." The Transylvanian variety has been described by 

 M. Haidinger, von Hauer, and R. Hoffmann (Jahrb. Imp. Geol. 

 Reichsanst. 1855). Another variety was found several years ago 

 in the Rhine Provinces by Professor Noeggerath, whose views con- 

 cerning this substance are identical with M. Haidinger' s. It occurs, 



