128 



THE GEOLOGIST 



long must we accord to them their proper position in the 

 arrangement of mineral substances, when their presence in 

 any ore produces a character which is solely attributable to 

 them. In every system of mineralogy founded upon che- 

 mical composition, a place is granted to those minerals, in 

 which a particular effect is produced by the admixture of an 

 acid of any kind, under the class of the base upon which the 

 action has taken place ; but in the system before us, it 

 appears that the several positions are accorded on the proof 

 of the existence of the agent and not according to the base. 

 Thus under the family of Alwninides, we have spinel and 

 graphite associated. In the family of siderites, we have 

 oligistic iron and franklimite ; and under the term Arsenmres, 

 we find the various associations of that agent with unde- 

 composed mineral bases, as silver, antimony, lead, nickel 

 and so forth. Nor do we deny that this is a very con- 

 cise arrangement ; but one argument is deduced from the 

 conviction that, (as we have stated before) so long as the 

 qualificative components themselves are recognised as unde- 

 composed elements, so long must they be considered the 

 qualificative constituents, and the ore or mineral rank ac- 

 cordingly in the arrangement, else any person studying the 

 productions of nature, so far as regards the mineral kingdom, 

 would, without minute study, leave with a false impression 

 that the rarer metals did not exist in a state of nature, but 

 were only the results of chemical research ; upon these 

 grounds then many of the metals, the most general in 

 their occurrence, would yield their rank to others with 

 which they are almost always found in connection. We 

 quote this as the broad argument, at the same time that 

 we record our estimation of the spirit of enquiry displayed 

 in M. Beudant's work, and the very concise manner in 

 which the information is conveyed to the student. 



