198 Nahtral History. [Chap. Ill, 



Saussure, jim., of Geneva ; Rinman and Ferber, of 

 Sweden j Pallas, of Russia; d*Acosta, of Spain; 

 Camera, of Portugal ; and Gioenni, Fabroni, and 

 Spallanzani, of Italy. 



The us^ of the Blow-Pipe, for the purpose of 

 assaying mineral bodies in the dry zoay, was first 

 introduced by van Swab, a little before the mid- 

 dle of the century. The importance of this appa- 

 ratus in mineralogy, and the great ease with which 

 it enables the experimenter to conduct his investi- 

 gations, render its introduction by no means an 

 inconsiderable aera in the history of the science. 

 After van Swab, the Blow-Pipe was much im- 

 proved, and more extensively applied, by Cron- 

 fjtedt, Bergman, Rinman, Berkenhout, Black, and 

 several others. The great value of this invention, 

 in chemical and mineralogical inquiries, will ap- 

 pear from considering that the most intense de- 

 gree of heat may be obtained by it, with the ut- 

 most conveniency, in a few minutes, which can 

 $;carcely be obtained by means of a crucible in 

 many hours. 



While new systems of arrangement and of lan- 

 guage i|i mineralogy, and new means of facilitat- 

 ing experiments in this science, have been pro- 

 posed by different philosophers during the period 

 under review, immense additions at the same 

 time have been made to the old catalogues of 

 mineral substances. Linnaeus described about ^five 

 hundred different species. Since that time so many 

 discoveries of new substances have been made, 

 that the number of species now known is between 

 seven and eight thousand. Seven new kinds of 

 tarih have been discovered within the century 



