SIR JAMES HALL on the Consolidation of the Strata. 



have come, the following circumstance presented itself to my re- 

 collection at the moment, and promised to afford some assistance 

 to these conjectures. 



A few miles lower down the valley in which the above facts 

 were observed, at the distance of more than a mile from the sea, 

 and between two and three hundred feet perpendicularly above 

 it, there occurs a crag of sandstone, in which a numerous suc- 

 cession of strata are distinctly visible. Several of these beds 

 have yielded much to the action of the air, and, in dry weather* 

 exhibit a considerable white efflorescence, which has completely 

 the taste of common salt; and so remarkable is this circum- 

 stance, that the rock has acquired, in the country, the name of 

 Salt-Heugh. 



Here, then, it immediately occurred to me, was probably the 

 source of an abundant supply of the elastic substance or fumiga- 

 tor, whose action as a flux had been pointed out by the aggluti- 

 nations in Aikengaw above described. 



I conceived, that, if there were at the bottom of the sea a 

 bed of sand and gravel, drenched with brine of full saturation, 

 and that heat were applied to it from beneath according to 

 Dr HUT-TON'S hypothesis, the first effect would be, to drive the 

 water from the lowest portion of the sand, and to convert the 

 salt which remained amongst it, together with the sand, into a 

 dry cake. During this operation, or until the cake became 

 quite dry, the absorption of latent heat would prevent the tem- 

 perature from surpassing the boiling point of brine. But no 

 sooner was this dryness accomplished, than, I imagined, the tem- 

 perature of the mass would begin to rise above that pitch ; the 

 portion of it next the fire would gradually acquire a red-heat ; 

 that then the salt, being made by the heat in part to assume an 

 elastic form, would be sent in fumes through the dry cake just 

 described, and thus, by partially melting the contiguous parti- 

 cles, produce an agglutination. 



Such being my theoretical views, no time was lost in submit- 



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