FOR HIGH LEVELS IN THE EARTH S ATMOSPHERE. 



65 



We may further assume tliat the air pressure shown by tlie station barometer at 

 8 A. "M. equalled 28.496 inches of mercury.* 



Now, if the barometric formula for static conditions be assumed as sufficiently 

 exact for the assumed dynamic conditions, then the calculation of the four quantities 

 ITp;, py, E^; and I p, will be carried on in exactly the same way for the vertical through 

 Omaha, Nebr., on 23 Sept., 1898, 8 A. M., 7oth meridian time, as though the atmos- 

 phere had been in a static condition on that day. We might therefore here make 

 use of the tables given in the chapter on static conditions. In order to avoid unnec- 

 essary repetition, the values just given for tr for Omaha, 23 Sept., 1893, 8 A. M., 75th 

 meridian time, have been used as the basis for this illustration of static conditions. 

 The following values were found by the method previously described : 



n 

 n 

 n 

 n 

 n 

 II 

 n 

 n 



20 000 

 IS .150 " 



30 000 

 20 OCfl ■ 



40 000 

 30 000 " 



50 000 

 40 000 ■ 



60 000 

 50 000 ■ 



70 000 

 60 000 ■ 



80 000 

 70 000 



90 000 



SO 000 ■ 



TT 100 000 

 ^^ 90 000 ■ 



TTIIOOOO 

 '■'lOOOOO ■ 



TT 1 20 000 



'^uoooo • 



0.098 



0.666 



0.645 



: 0.629 



0.614 



: 0.603 



: 0.590 



: 0.577 



: 0.565 



: 0.555 



: 0.545 



P 18 550 " 

 1* 20 000 ' 

 /* 30 000 ' 

 i^ 40 000 ■ 

 P 50 000 " 

 P 60 000 ■ 

 P 70 000 ' 

 P 80 000 ' 

 .P 90 000 ' 



P\m ooo ' 



Pi 10 000 " 

 ^120 000 ' 



28.496 



28.398 



27.732 



27.087 



26.458 



25.844 



: 25.241 



: 24.651 



24.074 



23.509 



22.954 



: 22.409 



*Thi3 station-pressure is to be reduced to standard gravity since this redaction is considered as one of the instru- 

 mental corrections, see pp. 33 and 42. The correction to a self-registering aneroid should include this item. — C. A. 



