58 MINING mDUSTEY. 



Virginia curve occurs, the main quartz quickly expanded northward to its old 

 dimensions, carrying an immense bonanza. 



Comparing the two bonanzas north and south of this point, Atlas-Plate 

 7, it will be at once seen that the southern is more regular in form, while the 

 northern is larger and more important. 



Lying east of this North Savage body, and confined between the 661 and 

 768-foot levels below the datum-point, there occurred a more eastern quartz- 

 body, lying in contact with the actual eastern wall. This so-called "Potosi 

 strike" is shown on Atlas-Plate 7, relieved with a darker tint against the 

 Savage bonanza. Its horizontal section, on the plane of the Savage seventh 

 level, is indicated on Atlas-Plate 11. Lining this body on the west, and 

 defining it from the curved propylite horse, was an immense vein of clay, 18 

 feet in thickness. On the Savage seventh station, this quartz-body has 

 entirely given out. 



A section on the Savage north line is given in Atlas-Plate 10, showing 

 the bodies of quartz filling conchoidal fissures, whose convex sides are to the 

 east. The red quartz descends to a depth of 500 feet, and is firmer and less 

 easily mined than the parallel zone of white. The eastern body is wholly of 

 white quartz, and contains its ore in a limited segregation in the very heart of 

 the sheet. An important fissure, still further to the east, makes its first 

 appearance in the Gould and Gurry second station, 625 feet below the datum- 

 point. 



Turning now to the section through the Bonner shaft, Atlas-Plate 10, 

 a new wedge-like body of quartz is seen lying upon the syenite in the 

 upper levels, known as the Eldorado vein. This converges at the depth 

 of the Eldorado adit with what was the larger body of the Savage north 

 line. This connects in dej)th with the eastern vein, and forms a continuous 

 mass of quartz, widening to 170 feet. From the outcrop 310 feet down, is 

 contained a very remarkable bonanza, whose peculiar section in the Gould and 

 Curry is seen oh Atlas-Plate 10. A singularly complex figure, it is really 

 two vertical sheets, connected near their bottom by a diagonal joining-seam, 

 similar to that noticed in the northern Gold Hill workings. Here was the 

 richest and most productive of all the Comstock ore-ground. For five years 

 the chambers in this bonanza steadily yielded an immense revenue; and even 



