1825.] Climate of the Antediluvian World. 105 



warmer than the air of levels in which the miners work ; and this 

 fact is of itself, when added to Mr. Bald's observations on the 

 water in mines, sufficient to set at rest, for ever, the supposition 

 of the heat beino; ovvino- to the miners, their horses and liohts, 

 &c. The health of a miner requires a constant circulation of air, 

 which renders the heat of mines more remarkable. 



The average temperature of air at the mouth of the mine 



of Reyas, near that of Valenciana, was 69"4 



Air at the depth of 630 feet 92-7 



Mr. Bald very properly remarks, that the heat of coal mines 

 cannot arise from the decomposition of sulphurets, for these 

 never suffer decomposition in situ ; if they did, the greater part 

 of the coal mines in the world would have been destroyed by 

 spontaneous ignition. In the mina Purgatoria, the height of 

 which above the level of the sea is equal to the Pic of Teneriffe, 

 the air in the mine was C)7*o Fahrenheit. 



From the foregoing observations, it is evident that the eleva- 

 tion of a mine above the level of the sea does not regulate its 

 temperature as it does that of the surface. Water at the depth 

 of 1200 feet under the sea in the Killingvvorth Colliery, was 

 stated to be 74° Fahr. ; while the air at 436 feet deep in the 

 mine of Villapenda, in Mexico, and which is more than 3000 

 feet above the level of the sea, is 84*9. 



When the phenomena of the antediluvian Flora, and the laws 

 of vegetable life, are considered in connection with all that has 

 been adduced, we are necessarily led to the same conclusion to 

 which many celebrated geologists have arrived, partly from 

 taking a different road of inquiry, and partly from conjecture; 

 namely, that there is -a source of heat in the centre of the earth 

 itself which must be referred to, as the cause of the uniformity 

 of temperature of the ancient world. 



In regard to the first of these suppositions, it is most certain 

 that when the granitic crust is duly considered in all its analo- 

 gies, it is much more reasonable to consider it as a crystalliza- 

 tion arising from fire than as a crystalline deposit from a watery 

 solution. We have no proof that any fluid, such as water, is 

 capable of holding such an immense quantity of the most inso- 

 luble of all substances in soluliou, and indeed it is probable that 

 the waters which we.e destined to act so remarkable a part on 

 the surface of our globe were, in the beginning of time, of the 

 purest kind, having no saline or mineral contents whatever to 

 deposit. The experiments of Sir James Hall and others have 

 proved that earthy substances, when fused under great presBMre^- 

 are capable of taking on a crystalline texture; and observation 

 demonstrates that even when not under great pressure, the ele- 

 ments of feldspar, mica, amphigene, hornblende, pyroxene, aiiial- 



