v)t;t. ( 334 ) 



On the Examination of Mountains and Plains, with the view of 

 discovering previously tmknoicn depositories of useful Mi- 

 nerals. By tlie late Frederick Mohs, Councillor of Mines 

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

 Merit, &c.* 



When we enter a mountainous district or a plain, for the 

 purpose of searching for repositoi'ies of useful minerals, worthy 

 of engaging the attention of the miner, it is essential that we 

 should become acqviainted with its precise position and bear- 

 ings. With this view, the first thing to be done, is to ascer- 

 tain from good maps, the principal direction of the mountains 

 and the chief limits of the plains, so that we may in every 

 case be able to determine exactly the point where we are, 

 that is, that we may be prepared to judge of the position of 

 that point in relation to the whole district. It is also very 

 advisable, befoi"e proceeding to the actual examination, to 

 delineate a map on a large scale, inasmuch as the largest to- 

 pographical maps are not sufficient to afford the investigator 

 all the assistance which may be expected from this source. 

 This enlarged map is as it were the magazine in which we 

 are to deposit all the observations made during the actual sur- 

 vey, in order that, at the termination of the examination, we 

 may borrow from it data for the preparation of correct petro- 

 graphical or geognostical maps and sections. Most represen- 

 tations of this kind are so deficient in exactness as not to be 

 available for so important an undertaking as the one we are 

 now considering. 



When in possession of such a nia,p, the next operation is, to 

 seek out and ascend the most important and remarkable emi- 



have been colder tbiui the latter; while an opposite result might be obtain- 

 ed when tlic vegetable, killed by warm water, had exhaled its excess of 

 moistiu-e, by remaining for a time in the open aii-. Perhaps also the parti- 

 cular parts of the vegetables used may have had an influence on the dif- 

 ferent results in question. — Comptes Reiiclus, Januarij 13. 1840. 



* Translated from an interesting little work entitled " AnleHiing Zum 

 Schilrfcn," published in Vienna in 1838, by order of tlie Imperial Chamber 

 of Mines, &c. — Edit. 



