53° 



SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOL. 51 



This equation gives the quantity of energy consumed by viscosity 

 in the unit time within the space k. 



The coefficient of viscosity of the air may with abundant accuracy 

 for the purpose of our estimate be assumed to be 



k = 0.00002 kg mr 1 sec" 1 



In order to study a movement that takes place with a very large 

 amount of internal friction, or in order to greatly overestimate the 

 influence of this friction it will be assumed that each component 

 of the velocity, along the direction of each of the three rectangular 

 axes, increases or diminishes by 10 meters per second per kilometer 

 of distance traveled, so that 



10 m sec l 



1000 m 



Moreover it will be assumed that the last or negative term with 

 the factor § in the Stokes equation as given above is to be omitted. 

 Under these assumptions Stokes equation becomes 



dK 



dt 



= k f 0.0018 dk 

 = 0.0018 Kk 



dk 



Hence, for a column of the atmosphere standing on a square meter 

 whose height we will for further exaggeration estimate at 100,000 

 meters and whose volume is therefore io 5 m 3 we have 



— - (2 X 10- 5 ) (10 5 ) (18 X 10- 4 ) 

 dt 



- 36 X 10- k m 

 sec 3 



