THE 



EDINBURGH NEW 

 PHILOSOPHICAL JOURNAL. 



Summary of the most important Geognoatical Phenomena with 

 which it is necessary to be acquainted in Preliminary Mining 

 Operations. By the late Frederick Mohs, Councillor of 

 Mines at Vienna, and Knight of the Royal Saxon Order of 

 Civil Merit, &c.* 



It is quite natural that when we seek for any thing, we must 

 know what we are to seek for, and where we are to seek for it. 

 I shall afterwards speak of what is to be the object of our search. 

 The where determines the places in which preliminary mining 

 operations, or the investigations generally, are to be undertaken. 



These districts are either whole groups of moimtains or por- 

 tions of them, or they are low tracts of country, distinguished 

 by their external aspect, which lie between two or more moun- 

 tain groups, and separate these from one another, generally by 

 means of inconsiderable inequalities of surface, which gradually 

 become lower, and finally disappear. They are termed plains. 



A mountain group is composed of mountain-chains, which, 

 in a certain order, or by certain combinations, form more or 

 less considerable elevations above the surrounding more level 

 tracts, or above the level of the sea. Its external form depends 

 on its internal constitution, and is imdoubtedly very important 

 to the geognost in a general point of view. It is also not with- 



* Geognostical views similar to some of those advanced by the late M. 

 Mohs in this article, and in the other portions of the summary, afterwards to 

 be published, were proposed by us to the Wemerian Society in the year 1813 ; 

 and accounts of them are to be found in the 2d vol. of the Memoirs of the 

 Wernerian Society, the 1st vol. of the Philosophical Journal, and the early 

 volumes of Thomson's Annals. — Editor. 



VOL. XXIX, NO. LVII. JULY 1840. A 



