352 Summary Revicu: of the late I/west igatio?is 



one I have heard of was reported to me by Captain Hosken. 

 An accident having happened to a steam-enghie at the United 

 Mines, the water increased so much as to fill the levels marked 

 in the table 190 and 200 fathoms under the sxnface ; and thus 

 it continued lor two days. Immediately after it had been 

 pumped out, and before the miners had begun to work in those 

 levels, he ascertained the temperature of the ground in the 

 upper one to be 87^°, and in the lower one to be 88°. On 

 renewing his observations some days after the men had resumed 

 their work in these places, the heat had rather diminished than 

 otherwise." 



" It is worthy of notice, that the principal part of the work 

 is not carried on in the deepest part of the mines : on the con- 

 trary, there are often more workmen employed at twenty or 

 thirty fathoms above the lowest part, than in the deepest level. 

 If therefore the increase in the temperature were wholly the 

 effect of adventitious causes, that increase would be greatest 

 where those causes had their largest operation. But the facts 

 which I have detailed in the table prove that, however various 

 may be the operation of accidental circumstances, in different 

 parts of the mines, the temperature invariably increases with 

 the depth." 



Mr. Fox next gives the results of some observations made 

 in the spring of 1 820 by Mr. J. T. Price, of Neath in Gla- 

 morganshire, in three collieries in the neighboui-hood of that 

 place. " The thermometer was buried for many hours, from 

 one to two feet under the ground, at the bottom of each of 

 these collieries. In one of them, which was only 10 fathoms 

 dee}), the mercury stood at 50° ; in another, 36 fathoms deep, 

 it stood at 58° ; and in the third, which was 90 fathoms deep, 

 it stood at 62\" 



In order to controvert the opinion that the water in the mines 

 receives its heat from the metallic veins, while passing through 

 them, in whicli case, he remarks, " it would surely become 

 strongly impregnated with mineral substances," — Mr. Fox 

 states, that upon analysing some of the water from the deepest 

 part of Dolcoath, taken at 82°, immediately from the copper 

 •vein, he obtained from a quarter of a pint of it only half a 

 grain of residuum, consisting of sulphuric acid, some oxide of 

 iron, and a little lime. " I found," he continues, " a greater 

 proportion of the same substances in some water from a cross 

 level, at a distance from any vein, 200 fathoms deep, in the 

 same mine. Water from the bottom of the United Mines, of 

 the temperature of 82°, contained six grains of muriate of lime 

 in a quarter of a pint. Some water taken from the deepest parts 

 of Treskerby and Ting- Tang, was, from the former mine, very 



slightly 



