Ijffccts of Heat modified hy Compression. I4l 



Facts leading to such striking conclusions, however imper- 

 fectly observed, could not fail to awaken curiosity, and give 

 rise to a desire of tracing the history, and of investigating 

 the causes, of such stupendous events ; and various attempts 

 were made in this way, but with little success 3 for, while 

 discoveries of the utmost importance and accuracy were 

 made in astronomy and natural philosophy, the systems 

 produced by the geologists were so fanciful and puerile, as 

 scarcely to deserve a serious refutation. 



One principal cause of this failure seems tc have lain ia 

 the very imperfect state of chemistry, which has only of 

 late years begun to deserve the name of a science. While 

 chemistrv was in its infancy, it was impossible that 

 geoloiry should make any progress ; since several of the 

 most important circumstances to be accounted for by this 

 latter science are admitted on all hands to depend upon prin- 

 ciples of the former. The consolidation of loose sand into 

 strata of solid rock ; the crystalline arrangement of sub- 

 stances accompanying those strata, and blended with them. 

 in various modes ; are circumstances of a chemical nature, 

 which all those who have attempted to frame theories of the 

 earth have endeavoured hy chemical reasonings to reconcile 

 to their hypotheses. 



Fire and water, the only agents in nature by which stony 

 substances are produced, under our observation, were em- 

 ployed by contending sects of geologists to explain all the 

 phenomena of the mineral kingdom. 



But the knov/n properties of water are quite repugnant to 

 the belief of its universal influence, since a very great pro- 

 portion of the substances under consideration are insoluble, 

 or nearlv so, in that fluid ; and since, if they were all ex- 

 tremely sulullc, the quantity of water which is known to 

 exist, or thai could possibly exist, in our planet, would ba 

 far too small to accomplish the office assigned to it in the 

 "Neptunian theory*. On the other hand, the known pro- 

 perties of fire are no less inadequate to the purpose ; for va- 

 rious substances which frequently occur in the mineral king- 



» Illustrations of the Iluttorim Theory, by Mr. Professor Playfair, 4C0. 



doru. 



