266 MR. W. H. PINES ON THE VEETICAL TEMPERATURE 



the barometer will be accompanied on the average by a rise of 0'4 km. in the vain, of 

 . Il^ler this rule holds for the upper part of the barometnc scale M a matter 

 that must be left for future observations to settle. 



Value of TV 



Closely connected with the value of H, is the value of T, the temperature of the 

 air at the commencement of the isothermal. The values corrected for the annual 



variation are 



10-3 ll'O 12-4 12-3 km. 



15'0 12'8 13'0 C. 



H c 



8 '4 

 24'5 



21'4 



18'4 



Plotted 0,1 squared paper these are not quite linear, but a straight line can be drawn 

 that lies within less than a degree of the given temperatures everywhere. 



is nearly 3"'0 C. to 1 km. 



The rule holds for change of latitude, for H c is large and T c low near the equator. 

 It holds as shown above for barometric change, but fails for the annual variation, 

 since H e and T e both reach their maximum values in the late summer. No daily 

 change in the value of H c can be detected with certainty, but more observations are 

 required. 



Average Height reached and Distance run by the Balloons. 



In the following table column A gives the average maximum height, column B 

 gives the difference between the value of T c and the temperature at the highest 

 point, T, being the standard, and Column C the distance in miles of the place of fall 

 from the starting place of the balloon. 



The corresponding values for the various pressure groups are in the shorter table 

 on the right. 



TABLE IX. 



