1.36 MINERALOGY AND 



with the minerals which environ them. In detach- 

 ing specimens from these mines, they must take 

 care to leave round the principal metal, either 

 portions of the other metals which are associated 

 with it, or of the stony substances which often ac- 

 company it, especially those which are crystallised. 



If they find earths which contain the remains of 

 organised beings, such as the bones of animals, 

 shells, impressions offish and vegetables, they should 

 collect with care, specimens of these different 

 bodies, having them enveloped in a portion of the 

 earth or stone in which they were fixed. 



In case the traveller should find any traces of 

 volcanic origin, he should procure specimens of the 

 different substances thrown up by explosions, some 

 of which are in a state of stone like basalt, others 

 similar to glass like obsidian, others in a state of 

 scoriae. For those that are in prisms, care should 

 lie taken to note the form of these prisms, and the 

 extent they occupy in the soil. 



A ticket should be fixed to each specimen indi- 

 cating the name of the country where it was found, 

 the spot from which it was taken, the distance of 

 this place from, and its situation with respect to 

 any known town in its neighbourhood ; as nearly 

 as possible the nature and general aspect of the soil, 

 and its elevation above the level of the sea. 



Wherever warm or mineral waters are found, 

 care should be taken to fill phials with them, which 

 should be well corked and luted. 



