752 DESCEIPTIVE GEOLOGY. 



Nevada Basin, inasmuch as in the main drainage courses throughout its 

 entire length is there not only no perennial stream, but scarcely one run- 

 ning a hundred yards, a month after the close of the spring rains. A few- 

 small springs in Trinity and Black Canons, and in the early season one or 

 two others scattered through the granite belt, afford, when the necessary 

 precautions are taken to prevent the water from running to waste, a sufficient 

 supply for bands of stock. 



Willow Spring, on the old Emigrant Road, in Rabbit Pass, is the only 

 large one running all the year with any considerable stream of water. It is 

 clear, cold, but slightly sulphurous, and comes from the Jurassic slates in 

 the eastern foot-hills. Timber is scarce, only a few pines and junipers of 

 dwarfed and stunted growth being found high up on the granite rocks, and 

 in the more sheltered canons. 



As a winter range for stock of all kinds, these mountains afford excellent 

 pasturage. The easily decomposing granites and slates yield a good soil 

 for a nutritious bunch-grass; and a moderate snow-fall, a mild climate, the 

 shortness of the rigorous season, and the broken nature of the country, are 

 all favorable for grazing purposes. 



Geologically, the structure of the Montezuma Range in most of its 

 broader features resembles the ranges already described to the eastward, 

 between the Humboldt River and Battle Mountains ; that is to say, it consists 

 of Archaean masses composed of granite and crystalline schist, striking 

 approximately northeast and southwest, forming the nucleus of the range, 

 overlying which are Mesozoic strata, resting unconformably upon them. 

 Breaking through the older formations are the Tertiary volcanic eruptions; 

 in the northern portion of the range confined to small outbreaks mainly 

 along the foot-hills, while to the south they have been ejected in such vast 

 masses as to conceal, over the greater part of the area, nearly all traces of 

 former rocks. The most distinctive feature of the Montezuma Range is, 

 so far as observed, the entire absence of not only the Koipato quartzites, 

 but also of the Star Peak series, the lowermost strata exposed consisting 

 of slates referred to the uppermost beds in the West Humboldt uplift. In 

 the Havallah Range, the Koipato beds are largely developed, overlaid by 

 Star Peak Triassic. In the West Humboldt, the Koipato formation is 

 somewhat thinner, but overlaid by the enormous thickness of 10,000 feet of 



