68 EXPERIMENTS on WHINSTONE and LAVA. 



refift the expanfion of the carbonic acid, and to conflrain it, up- 

 on the principle of Papins digefler, to continue in combination 

 with the Hme. This compound feems to have entered readily 

 into fufion, along with the whinflone, but to have kept feparate 

 from it, as oil feparates from water through which it has been 

 diffufed, thus giving rife to the fpherical form, which the no- 

 dules of calcareoi;s fpar generally exhibit with more or lefs re- 

 gularity *. 



This circumftance accounts for an appearance which has mif- 

 led fome of the early obfervers of our minerals. Many whin- 



ftone 



The whole of this fyflem appears to me well founded, except in what regards the 

 removal of the fuperiiicumbent mafs, which has been performed, 1 conceive, in a 

 very different manner. I am inclined to agree on this point with M. Pallas, M. 

 DE^AUSSURE, and M. Dolomieu, and to believe that, at fome period very re- 

 mote with refpeft to our hiftories, though fubfequent to the induration of the mine- 

 ral kingdom, the furface of the globe has been fwept by vaft torrents, flowing with 

 great rapidity, and fo deep as to overtop the mountains ; that thefe torrents, by re- 

 moving and undermining the ftrata in fome places, and by forming in others im- 

 menfe depofits, have produced the broken and motley ftrufture, which the loofe 

 and external part of our globe every where exhibits. 



In the Alps and in Sicily I have witnefled feveral of thofe curious facls, upon 

 which M. DE Saussure and M. Dolomieu found their opinion, and which feem to 

 juftlfy their conclufions. I have likewife obferved, in this country, many pheno- 

 mena which denote the influence of fimilar agents. Lord Daar, who joins me 

 in agreeing with Dr Hutton in almoft every article but this, has added great 

 weight to tlie argument by fome general obfervations on lakes, and by fome 

 very interefling fafls which he has obferved in the Highlands of Scotland. We 

 propofe to purfue this fubjeft, and to lay the refult of our inquiries before the So- 

 ciety. Dr Hutton, in the fecond volume of his "Theory of the Earth, has taken 

 great pains to refute all that has been faid about thefe torrents ; but, in my opinion, 

 their exiftence is not only quite confident with his general views, but feems dedu- 

 cible from his fuppofitions, almoft as a neceflary confequence. When the flrata, ac- 

 cording to his fyftem, were elevated from the bottom of the fea, the removal of fo 

 much water, if not performed with unaccountable flownefs, mufl have produced tor- 

 renis, in all diredlons, of exceffive magnitude, and fully adequate to the effefts I 

 have thus afcrlbed to them. 



* The modifications of the aflion of heat, occafioned by preflure, which have 

 been taken into account by no geologift but Dr HuTTON, diftinguiih his theory from 

 all other igneous theories. 



