MORLOT ON THE TREBICH GROTTO. 61 
mulates in the interior of the mountains, and swelling up to a great 
height drives out the air, often with much violence, through the nar- 
row fissures and the caverns connected with them above. This cir- 
cumstance often shows that holes which on the surface are very small, 
are yet continued deep into the interior. Many of these holes were 
lately examined, and extensive wanderings undertaken below ground, 
with the view of discovering in the vicinity of Trieste some subter- 
ranean stream which might supply the town with water. At length 
an opening of no great width, but sinking perpendicularly into the 
ground, was discovered at Trebich, about a league north-east from 
Trieste, which was followed out with great perseverance. The fissure 
sometimes expanded into a wide cavern, sometimes contracted to a 
rent of scarce a finger’s breadth, and requiring great labour in blow- 
ing up the rocks, to enable the workmen to proceed; but it never 
closed up entirely, and some opening, however small, always remained, 
keeping up the connexion. Sometimes it separated into branches, 
but by always adhering to the one from which the current of air 
issued, a very considerable depth was soon attained without any great 
deviation from the direct course. Once, in a wide part of the opening, 
all trace of its continuation was lost, and many attempts to recover it, 
by blowing up the rock, had been made in vain, when the workman, 
Antony Arich, an intelligent miner from Carinthia, heard during the 
night a loud roarmg and howling, and concluded that the water in 
the interior, rising suddenly in consequence of heavy rain, was forcing 
the air through some narrow opening, and thus discovered near the 
roof of the cave a small fissure, which again led in the right direction. 
At length, after eleven months’ hard labour, Arich reached a very 
large and extensive grotto, 270 feet high, at the bottom of which, 
1022 feet below the surface of the earth, and 62 feet above the 
sea-level, a considerable stream of running water was found. This 
lowest opening is still in the bituminous limestone of the Karst, but 
contains on a stair-like elevation a considerable deposit of sand, pro- 
duced by the destruction of the sandstone and slate, over which the 
river has run in its course aboveground. The water enters the grotto 
through a low vault, and flowing among the numerous large blocks 
which have fallen from the roof, expands into a long narrow lake, on 
which a small raft was formed, to explore its further course, and is 
at length lost under a vault which, descending below the surface of 
the water, put a stop to the investigation. During heavy rain the 
water has been alréady seen to rise 240 feet; but to judge from an 
old float of a mill-wheel found in a higher part of the hole, it must 
sometimes attain a height of 300 feet above its usual level. 
(J. N.] 
On the Vicinity of ScHEMNITZ and KREMNITZ. 
By Prof. v. Perrko. 
[From ‘ Haidinger’s Berichte,’ vol. iii. pp. 208, 269.] 
ProFressor PetrKo endeavours to prove that the whole trachytic 
