278 On the Identity of Sllex and Oxygen* 



the most obvious source from whence the oxygen could have 

 been derived, but, were there any objection, it must be also 

 noticed that the ore itself had been originally enveloped in 

 silex (gangue quartzeuse), so much so, that what was su- 

 perfluous and extraneous adhered so closely, that it was 

 with great difficulty these gentlemen could detach it, so as 

 to divide it from the mere ore. 



The sulphur, lime and metal, which often constitute the 

 lead-ore, called galena, or sulphuret of lead, are accompanied 

 by silex ; and the general neutrality of the whole mixture 

 maybe ascribed to this, the common oxidizing element; 

 for, if it be not in the ore itself, it is so very contiguous, 

 that the matrix is, either entirely or in part, composed of 

 this substance. 



Magnesia, another of the most abundant of the earths, 

 is never found in a pure state, but, like all others, is either 

 blended with an acid or concealed by means of silex ; and 

 whether it be alone or accompanied by alumine, lime, or 

 any other substance, this is invariably the state to which it 

 is reduced. Thus, in asbestos, the magnesia, alumine and 

 lime are sufficiently degraded to be deprived of all external 

 peculiarities, and to shun the usual tests ; for, though nearly 

 one half of this mineral is composed of these three bodies, 

 they are more than counterbalanced by the other element. 



Potash and soda, which exist in somany situations, and are 

 found to be more abnndant than had formerly been suspected, 

 appear to constitute one of the principal ingredients in va- 

 rious mineral bodies, particularly in the more huge masses of 

 matter, in the primitive rocks and mountains, and, probably, 

 in other substances, in which it has hitherto escaped our at- 

 tention. These are to be considered, not only to be in the 

 same predicament as the earths, but, being possessed of 

 higher powers and more considerable energy as salifiable 

 bases, they furnish more conclusive examples for elucidating 

 this subject, and more openly evince the oxgyenating efficacy 

 of silex. In all substances in which these are found, there 

 is no appearance of an alkali ; they have, till very lately, 

 withstood all research ; and even their ready solubility in 

 water, the peculiar taste, which, it will be granted, is of the 



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