164 Mr. J. A. Phillips on the Composition 



[terminations, 

 fl mirO - . L f*663 : l'O, mean of two de- 



B .. . 2 „ after mt « r P°- | -802 : 1-0 



Katio ot Jo I sing and the J . Q1 ~ -, >n 



removal of j . 851 . i-q, me an of three. 



resistances , 

 5 



the screen, ^. 868 . 1 . Q 



In a drier atmosphere the maximum, which was still as ra- 

 pidly attained, was retained with tolerable constancy. Probably 

 the diminution of the effect after the maximum had been reached 

 may have been due to the slower dissipation of the film of mois- 

 ture, and to its re-formation under the alternations of temperature 

 which accompanied the alternations of light and darkness. 



I regret that I shall not have leisure to pursue this subject 

 for some time, and am therefore obliged to leave off these expe- 

 riments in their present incomplete state. 



January 1874. 



XXII. Note on the Composition of certain Mine Waters. By J. 

 Arthur Phillips, M.Inst.C.E., F.G.S., F.C.S., $c* 



SINCE the publication of a paper in which I attempted to 

 show that the waters of the thermal spring at Huel Seton 

 Mine are probably derived from the seaf, two other waters from 

 deep Cornish mines have been analyzed in my laboratory. 



The first of these was from the 212-fathom level at the Phoenix 

 Mines near Liskeard, where it issues from the lode at a tem- 

 perature of 65° F. This mine is in granite, and at one time 

 produced large quantities of copper ores, but has for the last ten 

 years been principally worked for tin, which is obtained from the 

 same veins which were formerly wrought for copper. A large 

 portion of the vein above the point from which the water for 

 analysis was collected had been removed some years previously. 



The following results, in grammes per litre and grains per 

 gallon, were obtained by analysis. 



* Communicated by the Author. 



f Philosophical Magazine, July 1873 



