Neiu PuhUcattons. 171 



\vith probability of fiiccefs, only on the fides of primitive 

 mountains, in the vicinity of mountains of argillaceous por- 

 phyry, amidlt fanditone and fliale bearing the impreffions of 

 vegetables, under alternating Itrata of linieftone and fand- 

 ftone, or amidll ftrata of trap, or whin with fandftone or 

 clay. 



Common Salt and its Mines are the fubjefts of the tenth 

 E{fay. The fea is here reprefented as owing its faltnefs to 

 fimple faline fubftances held in folution in it ever fince the 

 creation. The mines of rock-falt which have been in differ', 

 ent places difcoveredj are faid to have all originated from the 

 detention and evaporation of fea-watei*. Salt-fprings and 

 lakes are related to contain and pour forth, from time to 

 time, quantities of faline matter, which, when fubjefted to 

 calculation, cannot but, by their magnitude, excit.* the 

 greated aftoniftunent. Thefe general fa6ls are Unfolded 

 amid an exceedingly curious and intertlling difplay of par- 

 ticulars. 



The eleventh Eflay is on the fubjeft of Metallic Mines. 

 it relates, that all the metals muft have exifted perfe<Sl and 

 uncontaminated in the chaotic flood. Gold is found natu- 

 rally pure oftener than any of the other metals. Silver is 

 much more frequently mineralifed by fulphur, and alloyed 

 with copper) antimony, kad, mercury, tin, or bifmuth. 

 Nature prefents Itiil lefs of pure copper than of pure filver: 

 the ores of copper are fcarcely ever free from fulphur. Of 

 pure native iron there are few or no fpecimens, except cer- 

 V\in mafles found in Siberia and Peru, whirh feem to have 

 been originally agglutinated by petrol, and left bare by the • 

 diflblution of the maflbs of other matters which once fur- 

 hounded them. Isfative bifmuth accompanies the gray and 

 the bright white ores of cobalt. Native arfenic is found only 

 in the veins of primeval mountains : native mercury occurs 

 in clay in mountains of fecondary formation : fulphurated 

 ores have been formed at a time when fulphur as well as 

 metals were in a ftate of extreme fubdivillon in which they 

 were much more foluble in fluids than they are at prefent. 

 The cryt^allifation of metallic ores was the confequence, in 

 foiiie inltarices, of the diminution of the watery menftruum, 

 Z 3 iu 



