408 Mr. J. A. Phillips on the Connexion of certain 



On examining pyrites forming the substance of fossilized 

 trees found in the deep diggings at French Corral, California, 

 I was unable to detect any decided traces of gold; but assays 

 of several specimens of the cementing pyrites of an auriferous 

 deposit of tertiary age, and probably belonging to the later Plio- 

 cene period, invariably afforded a small amount of that metal. 

 A microscopical examination of the gold in this pyrites showed 

 that the fragments were frequently angular, and apparently un- 

 waterworn. 



In order to ascertain whether waters traversing mineral veins 

 contain an appreciable quantity of any of the constituents of the 

 lodes through which they pass, I subjected three specimens, 

 obtained from deep Cornish mines, to careful analysis. I am 

 indebted for the samples operated on to Mr. Francis Oats, of 

 Botallack, a member of the Miners' Association of Cornwall, who 

 in each case collected about six gallons of the water issuing 

 from the bottom of a level, where the lode beneath remained 

 intact, in clean and carefully stoppered glass bottles. 



Water from Balleswidden Mine. — This was collected from the 

 bottom of a sink below the 50-fathom level on the " Pye Lode," 

 which is one of a series of veins having a south-easterly direction 

 occurring in granite, and which are chiefly composed of quartz, 

 mica, schorl, and oxide of tin. The nearest known junction of 

 granite with clay-slate is at a distance of about one and a half 

 mile from the point from which the water was collected. 



The following are the results, in grains per gallon and grammes 

 per litre, obtained by analysis. 



Specific gravity not taken. 



Total solid contents 13*59 grains 



per gallon. 







Grains 



Gramme 





per gallon. 



per litre. 



Chlorine . 



. 3-59 



•0512 



Sulphuric acid (SO 4 ) 



. 4-80 



•0685 



Silica .... 



. -70 



•0100 



Alumina . . . 



. trace 



trace 



Lime .... 



2-80 



•0400 



Magnesia . 



. trace 



trace 



Iron* 



•08 



•0011 



Alkaline chlorides 



. 6-10 



•0870 



Potassium ... 



•49 



0070 



Sodium .... 



2-02 



•0288 



Carbonic acid 



trace 



trace 



toria, by Alfred K. C. Selwyn and George H. F. IJliich, p. 56. Mel- 

 bourne : 1866. 



* By potassium dichromate. 



