On the Manttfacture of Glass ^ ^c, 101 



traded but little attention, those last-mentioned rocks have 

 undoubtedly not been deposited precisely in the manner in 

 which we now find them. But still, it is chiefly the mas;5ive 

 crystalline siliceous mountain-rocks that we have in our eye, 

 and those namely which are found in our transition-formation. 

 As we are now about to apply the results of our foregoing ge- 

 neral views, it will be proper to touch also on a portion of the 

 other rocks of the same formation, whose formation stands in 

 certain relations of dependence to the massive rocks, or which, 

 when viewed along with these, may throw additional light on 

 the subject. 



In the course of this discussion, I shall follow the not un- 

 usual, tliough sometimes certainly, the not advisable method 

 of treating the subject in the manner as if it were supposed 

 that the author's own theoretical views were all determined to 

 be entirely correct ; and this plan will cause us to speak of the 

 metamorphoses that have been assumed, with as much cer- 

 tainty as vulcanists express themselves, when they designate 

 granite, &c. as products of smelting. This manner of pro- 

 ceeding will, I hope, in the present instance, meet with so 

 much the more approbation, when I explain tha* I do not wish 

 to exalt my theory farther, than merely to regard it as a cos- 

 tume, a dress, with which we must clothe the new facts we 

 have discovered, since these, in their natural nakedness, could 

 not be introduced, or expect to be received, into the halls of 

 science. 



( To he concliided in our next Number). 



On the Manvfacture of Glass, Porcelain, and False Stones, as 

 known to the Jncient Egyptians. With Illustrative Figures." 



Of the progress of the ancient Egyptians in many useful 

 branches of art, we have unquestionable proofs in the monu- 



• We have to express our thanks to Mr Murray of Albemarle Street, for 

 his kindness in facilitating the transference to our pages of the woodcuts il- 

 lustrative of the Egyptian manufacture of glass. The present article is ex- 

 tracted from Mr Wilkinson's very valuable and elaborate work on "The 

 Manners and Customs of the Ancient Egyptians." — Edit. 



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