94 MINING INDUSTET. 



found the two walls coming into close contact, with no appearance of the 

 re-opening of a downward chamber, the very existence of such deep-seated 

 fissure was more than doubted. The great structural puzzle of the lode for 

 three years has been to find the vents through which the quartz ascended 

 and filled the fissures of the ore-channel. Within the last year a new aspect 

 has been put upon the whole question. In Gold Hill, the west clay-seam, 

 after steadily and uniformly approaching the east quartz to within 60 feet of 

 actual contact with it, has now opened downward into almost exact parallelism 

 with that body. At the lowest working in the Virginia group, at a point in 

 the Hale and Norcross, or directly within the widest eastern expansion of the 

 Virginia chamber, the east fissure opened more and more into an inclined 

 position, until now, in the deepest works, the walls are approaching parallel- 

 ism, and the conditions assuming more and more those of a simple fissure. 

 In the previous pages reasons have been given which seemed to forbid 

 the idea of the quartz being segregated by lateral secretion in situ. If it 

 ascended from the depths below, as there can be no doubt it did, it must have 

 had a very considerable channel, for its immense volumes forbid the. idea of a 

 slow seepage through a very contracted channel. It is possible for the quartz 

 to have risen either through one general fissure, or to have found an entrance 

 into the gashes of the ore-channel through two or three narrow chimneys. 

 Had the former been the case it is difficult to conceive any reason for the 

 peculiar disposition of the bonanzas. Had it been equally easy for the quartz 

 to ascend at any part of the lode, and had the nature of the fissure given free 

 vent to ascending currents either of water or metallic vapors, there would 

 seem to be no reason why the bonanzas would not have been more equally 

 distributed through the quartz. Decidedly the most remarkable feature of 

 the silver distribution is that, with an immense surface expansion, it focuses 

 downward in three points, at Gold Hill, Virginia, and Ophir. This is some- 

 what due, no doubt, to the fact that the ore-channel stands at a much greater 

 angle than the west wall, and that the junction of these two systems of fissur- 

 ing would naturally produce some barriers to the upward transit of material. 

 It is dangerous to hazard'a conjecture as to the mode of occurrence below; it 

 is working altogether in the dark. The indications at present are insufficient 

 to warrant any well-grounded conclusion. This, of course, offers but little 



