194 



other circumstances as were admissible in a view 

 so brief. As the object of this sketch, is to facili- 

 tate the researches of the student respecting the 

 name or place of a specimen, I have been little 

 scrupulous about the nature of the characters 

 selected, provided they conduced to the main end, 

 utility. Mineral and geological characters, nega- 

 tive distinctions, and empirical marks, are there- 

 fore indiscriminately used; that, in consulting 

 this abstract, the reader may be enabled, in some 

 degree, to limit his search through the several 

 Synopses among which his specimen will some- 

 where be found more accurately described. To- 

 wards accomplishing this object, additional assis- 

 tance is afforded by the arrangement in the 

 eleventh chapter. No expedient ought to be 

 despised if it serves to diminish the labour and 

 remove the doubts by which a beginner is so often 

 disgusted in the commencement of his career. If 

 it has been sometimes found necessary to repeat 

 these general characters in the preliminary re- 

 marks to the different synopses, the present col- 

 lective view of them was not the less requisite. 



