372 QUICKSILVER DEPOSITS OF THE PACIFIC SLOPE. 



disappeared as depth increased. Besides tlie usual pyrite and marcasite, 

 millerite is found in fine, bronze-colored needles on the 300-foot level. This 

 mineral has been observed as microscopic crystals in the slides of ore from 

 several of the mines in California, but not elsewhere in crystals visible to 

 the naked eye, so far as I know. 



Napaiite. — Tlio miuo coutaius much yellow, bituminous matter, usually of 

 a consistency similar to that of shoemaker's wax; indeed, it has actually 

 been emplo3'ed as a substitute for that useful material. It has been exam- 

 ined by Dr. Melville and turns out to be a new mineral. 



The substance is dark reddish brown and shows green fluorescence by 

 reflected light; by transmitted light, brilliant garnet red. It is interesting 

 to note that the green fluorescence disappears in a great measure on ex- 

 posure to the air, evidently with a loss of some very volatile constituent. 

 The specimens from which the material was obtained for analysis had un- 

 dergone this change, only a few smaller fragments exhibiting the original 

 color. The ethereal solution is reddish brown, with green fluorescence, and 

 both this solution and the solid resin are highly refracting. The luster is 

 resinous and the hardness about 2. Ibis brittle, but by the warmth of the 

 hand may easily be molded and drawn into long threads. It is not elastic. 

 The fracture is conchoidal. It begins to fuse at 42° C. and becomes liquid 

 at 46° C; it boils above 300° C; at 130° C. a heavy, colorless oil distills 

 over, yielding an aromatic odor ; then at a higher temperature yellow- 

 brown vapors rise with a peculiar suffocating odor, and finally a heavy, 

 dark red oil condenses, much resembling coal-tar in smell. The boiling- 

 point of this last product is not far below the temperature of 350° C. 

 Many intermediate products were obtained by fractional distillation, but 

 the yield was very small below 236° C, above which colored distillates 

 were collected. At the temperature of softening of the glass boiling-flask 

 a small amount of carbonaceous matter remains, showing that decompo- 

 sition in part results Bromine attacks the resin with deposition of carbon. 

 Ether dissolves it completely in the cold; so, also, does oil of turpentine, 

 but not so readily; cold alcohol takes up but a small quantity. It is com- 

 bustible and yields absolutel}'^ no residue. A small amount of sulphur was 

 detected in one s.iinpic, but its aljsence in others proved that its origin was 



