respecting the Temperature of Mines. 95 



the temperatures of three mines mentioned in his first memoir. 

 As each communication principally relates to the phaenomena 

 of the same mines, it will be most convenient and useful to 

 give the substance of them all under one head, in a connected 

 form. 



" So far back as the year 1812," Mr. Moyle informs us in 

 his first paper, " my attention was drawn to the consideration 

 of the temperature of our mines, from the circumstance of 

 meeting vn\h water in different levels which felt of various de- 

 grees of heat. From this time I began to collect notes of the 

 temperature of several mines ; but as they were made merely 

 for my own gratification, without any idea of their meeting the 

 public eye, I do not feel sufficient confidence in them to state 

 ihat they are entirely free fi'om error, as it is possible that 

 many adventitious circumstances were disregarded, which 

 might have affected the result. I shall, however, select only 

 a tew of my early experiments, making a distinction between 

 them and those made within the last twelve months, which 

 were made with all possible care and exactness. This I have 

 considered more particularly necessary', as the subject has be- 

 come of late a matter of serious inquiry, and various opinions 

 have been formed as to the relative temperature of the interior 

 strata of our earth, and its causes." 



" As it is only by comparing the different results of the ex- 

 periments of individuals that the truth, or an approximation 

 to it, can be elicited, I conceive too much attention cannot be 

 paid to the mode in which those experiments are conducted. 

 With respect to the temperatures now given, where there has 

 been any degree of uncertainty in the result, they have been 

 taken twice or thrice in the same spot, by difi'ei'ent methods, 

 such as burying the thei'mometer in the earth, or rock of the 

 gallery, — in the full stream of water issuing from the veins, — 

 by allowing it to remain 15 or 20 minutes during each obser- 

 vation, — and by the correspondence of two or three thermo- 

 meters at the same time." 



Mr. Moyle now details his experiments, the results and cir- 

 cumstances of which we have arranged into the following table, 

 appending to it, in remarks and notes, such particulars as were 

 found unsusceptible of tabular abbreviation : into this table, 

 likewise, we have introduced some facts given by the same 

 gentleman in his second paper. 



Tern- 



