30 GEOLOGICAL MEMOIRS. 



an average inclination of 62°, a height of 54 feet, and a breadth of 

 60 feet, is completely coated with hard ice a foot thick, and is 

 surmounted by a pyramidal mass of ice, 24 feet high (reaching to 

 the roof). Behind this natural wall is a second cave, 144 feet long, 

 60 feet broad, and 36 feet high, the bottom of which is covered by 

 crusts and stalagmites of ice, and from its ceiling hang icy stalactites. 



Both these caverns have their outer portions nearly corresponding 

 in position with the magnetic meridian, and afterwards bifurcate 

 into two branches, the western of which is the larger one, probably 

 joining at some distance the other and less extensive eastern branch. 

 The branches of each cavern terminate in high ascending chimneys 

 or pits ; the pit of the Taubenloch reaching upwards to the height 

 of 96 feet. 



The temperature of the ice-cave itself is 1°*7 K. ; it falls to 1°'4 R. 

 in the gallery behind it, out of which comes a strong current of air. 

 This gallery is generally dry ; ice occurs in some parts of it. A 

 small pond of water at the end of the eastern lateral branch was 

 found to have a temperature of 2°'d R. [Count M.] 



On the Metalliferous Deposits m Upper Carinthia. 

 By M. LiPOLD. 



[Proceed. Imp. Geol. Instit. Vienna, April 18, 1857.] 



The following observations have reference to that portion of Upper 

 Carinthia surveyed by M. Lipoid in 18.56. The well-known quick- 

 silver-mines of Idria are being worked on a thick vein (Stockwerk), 

 dipping N.E., and belonging (as repeated chemical analyses seem 

 to prove) to the Gailthal or the Alpine Carboniferous strata. These 

 mercuriferous rocks contain more or less silica and alumina, combined 

 with a considerable proportion of carbonate of magnesia. Mercury 

 occurs likewise near St. Oswald, and near St. Thomas (Laak) on the 

 boundary between the Werfen- and the Gailthal-strata ; and it has 

 been also recently found in the deeper portions of the Knaponsche 

 lead- veins. 



Outcrops of copper-ores are frequent in Upper Carniolia, especially 

 west of Laak, towards Kirchheim in Goritzia. The ore worked by 

 M. Kanitz, with much perseverance and a good prospect of success, 

 is generally massive and variegated sulphuret of copper, with from 

 40 to 50 per cent, of metal, in lenticular or thick layers, on the 

 limit between the Werfen- and Gailthal-strata ; yellow sulphuret and 

 grey copper-ore only occasionally occurring. A cupriferous deposit, 

 here and there of several fathoms' * thickness, has been opened to an 

 extent of 240 feet, and to the same depth. Other layers, in the 

 same geological position, contain only yellow copper-pyrites, and are 

 still but little worked. 



Lead occurs, in the form of galena, in a vein of quartz and quartz- 



* An Austrian " klafter " is somewhat more than an English fathom. 



