GENERAL EEPOET. xix 



March, February, and January, of 32.8° ; giving a mean annual rate of 51.5°. 

 The monthly means range from 28.6° in January to 76.2° in August. At 

 the more elevated stations in Northern Nevada, (Fort Euby, Camp Halleck, 

 Camp Scott, Camp McDermit, and Camp McGarry,) the corresponding 

 averages appear very nearly four degrees lovs^er, October only having a dif- 

 ference of twice that amount and ranking after the month of May instead of 

 before it. On the other hand the temperature at Fort Churchill on the 

 Carson River in Western Nevada, at an altitude of 4,284 feet, from March 

 to September ranged from tw^o to four degrees higher than at Camp Douglas, 

 though from October to December nearly as much lovs^er. 



During the vsfinter of 1867-68 at Carson City, the month of December, 

 as stated, was mild, with an average daily maximum of not less than 

 50° and a mean minimum of about 20°. January, on the other hand, was 

 remarkably cold, with a mean maximum of about 26° and a corresponding 

 minimum of 10°, the observed extremes of temperature being 35.5° and 

 — 10.0°. This cold term continued through February, the mean daily maxi- 

 mum of that month being about 35° and the minimum below 10°, and for 

 the first half of the month 6°, the extreme maximum observed being 50.5° 

 and the extreme minimum — 16.0°. It is very notable that in Virginia City 

 on the eastern slope of Mount Davidson, twelve miles distant and at an 

 elevation nearly 1,500 feet greater, the temperature was uniformly and con- 

 siderably higher. 



The thermometrical observations taken in the field in 1867 and 1868 

 were not sufficiently continuous at any one station or altitude to authorize 

 any very positive general deductions. The following series of readings, or 

 when possible means of readings, will fairly illustrate, however, in some degree 

 the daily range of temperature, the usually great dryness of the air as 

 shown by the differences of the dry and wet bulb thermometers, the heat of 

 the direct sun's rays as shown by the black bulb thermometer, and the amount 

 of night radiation as shown by the minimum thermometer, while some other 

 matters are noted as of interest in this connection. The first table is con- 

 fined mainly to the low valleys of Western Nevada, the second to the higher 

 valleys of Eastern Nevada, and the third to the mountain summits. It should 

 be stated that the wet bulb was always fully exposed to whatever wind was 

 blowing, as thus securing reliable indications of the actual evaporating power 

 of the air under existing conditions. 



