72 JOURNAL OF THE 



sions of fluids and gases have often been observed nud of 

 remarkable quantity. Crystals containing inclusions of fluids and 

 gases are not uncommon, but crystals having such inclusions 

 plainly visible to the naked eye are rarely found. 



A brief description of a very remarkable '' pocket" of these 

 fluid-bearing crystals opened out some seven years ago at the 

 now well-known gem locality in Sharpens Township, Alexander 

 county, would perhaps be of interest to record here.* 



It was while prospecting for new veins bearing emeralds that 

 this pocket was unexpectedly discovered. A narrow drift of 

 quartz fragments, with small flakes of mica, was the only sur- 

 face sign noticeable. At the head of this drift a shaft was sunk 

 to a depth of nineteen feet, with the following interesting 

 results : 



The drift, within a foot of the surface, took shape as a solid 

 vein of quartz, which rapidly widened until, at six feet depth, 

 it had attained a width of fully three feet. Within the next 

 two feet the pocket nature of the vein had become apparent by 

 the presence of hard lumps of red clay, within which small crys- 

 tals of quartz were found. 



The vein for the next foot was almost entirely composed of 

 this hard red clay. Then, to our great astonishment, one of the 

 miners, striking his pick very forcibly, saw it disappear wholly 

 from his sight. Naturally he was alarmed. We all thought for 

 a time the safest place was at the top of the shaft. Feeling from 

 past experiences at the locality tliat a cavity of not very 

 unusual dimensions was about to be opened to our view, we 

 descended and resumed the work. 



Procuring a long stick, I probed this cavity, so as to ascertain 

 its size, this being a necessary precaution to work it out properly 

 and safely. 



It was thus shown that the pocket was about three feet wide, 

 seven feet long, and at that time about three feet deep, though 

 I could push the stick quite deeply into the clay at the bottom. 



*Trans. N. Y. Acad. Sei., March, 1882. 



