106 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



tions affect very sensibly both astronomical, meteorological, 

 and hypsometric labors. Professor Plantamour was among 

 the first to show that observations of the barometer taken 

 simultaneously at two distinct stations ought to enable us 

 by calculation to arrive at the average temperature of the 

 intervening atmosphere. Among those who have lately ap- 

 plied this method is Mr. Schott of the Coast Survey, who 

 has, from observations made about fifty miles northwest of 

 San Francisco, calculated the temperature of the air between 

 two stations occupied by Mr. Davidson. As the results of 

 these studies, it appears that the average temperature of 

 the air between two stations differing 2000 feet in altitude 

 remained sensibly constant throughout the entire day, as 

 though the sun's rays passed through it without apprecia- 

 bly heating it ; while, on the other hand, the thermometer at 

 the two stations respectively rose to a maximum at 1 P.M., 

 and fell to a minimum in the morning and evening. The 

 daily variations of temperature seem, therefore, to be con- 

 fined mainly to the layer of air in close proximity to the 

 earth's surface. The corrections to be applied to the ob- 

 served thermometers, in order to obtain the true tempera- 

 ture of the air, varied regularly throughout the day, and 

 are decidedly larger than those obtained by Professor Plan- 

 tamour at Geneva. M. Schott, in explanation of this phe- 

 nomenon, suggests that probably the 20 or 30 per cent, of 

 total solar radiation which is absorbed by the atmosphere 

 is consumed in the processes of expansion and evaporation ; 

 and thus gives no sensible heat. Coast Survey Report^ Ap- 

 pendix XL, 1871. 



THE UPPEE CURRENTS OF THE ATMOSPHERE. 



The tipper currents have been much neglected by meteor- 

 ologists until recent times, when the extensive weather-maps 

 published in Europe and America have enabled proper at- 

 tention to be given to their study. Some of the important 

 laws relatinor to the movements of the cirrus clouds were 

 apparently suspected by Redfield, and were in a general 

 way predicted by Ferrel ; but extended observations and 

 deductions are due principally to Clement Ley (1872), and 

 more recently to Hildebrandsson, the Director of the Mete- 

 oroloo'ical Bureau of Sweden. This gentleman states that 



