io6 Dr. Falconer on the Knowledge 



It is difficult to guefs what the compofition of 

 the fubftance here called glafs could be. It cer- 

 tainly could not be any vitrified body as fuch are 

 univerfally brittle. Sotne have thought it to have 

 been the luna cornea, or the calx of filver, made 

 by the diffolution of that metal in the acid of 

 nitre, and its precipitation by that of fait. But 

 this, though endued with confiderable flexibility 

 and tenacity, is not malleable to the degree here 

 reprefcnted. 



Pliny, however, appears to have left 

 A. D. 77. ^,g {he jYioft complete information con- 



Plinius . 1 r TT • • L 



obiit. cerning glafs. He mentions it as be- 



ing of Phsenician origin, as many other 

 great difcoveries have been. It v/as firft made of 

 fand found in the river Belus, a fmall river of 

 Galilee, running from the foot of Mount Carmel, 

 out of the lake Cendevia. The part of the fliore 

 where the fand was dug, did not exceed 500 

 paces in extent, and had been ufed many ages 

 before, for the fame purpofe. The report of its 

 difcovery was, that a merchant fliip laden with 

 nitre, or foffil alkali, being driven upon the 

 coail, and the crew going afliore for provifions, 

 and dreffing their viduals upon the fliore, made 

 life of fome pieces of foffil alkali to fupport their 

 kettles. By thefe means a vitrification of the fand 

 beneath the fire was produced, which affiarded 

 a hint for the manufacture. In procefs of time 

 the calx of iron, in form of the magnetical ftone, 



pam,e 



