ii WIND ATOMIC THEORY 195 



people there is no disturbance as one walks along 

 it ; but when a crowd meets in a narrow space, then 

 they jostle against each other, and quarrelling 

 arises. Similarly in this space which surrounds our 

 earth ; when many bodies have crowded a very 

 small portion, it is unavoidable that they should 

 jostle one another and be driven back and forward, 

 and be intertwined and squeezed. Hence results 

 wind ; the particles that were struggling have had 

 to give way, and after being tossed about and 

 remaining in suspense for a long time they at 

 length lean their weight toward one side. But when 

 a few bodies occupy a large roomy place, they can 

 neither ram each other nor be jostled by one 

 another. 



Ill 



THE falsity of this view may be inferred merely i 

 from the fact that wind by no means invariably 

 accompanies a cloud-laden atmosphere, and yet 

 more particles have gathered at that than at any 

 other time in a narrow space, where they * pro 

 duce condensation and heaviness in the clouds. 

 Besides, in the neighbourhood of rivers and lakes 

 cloud is frequent from the confinement and accu 

 mulation of particles, and yet there is no attendant 

 wind. Indeed, sometimes such a darkness over 

 spreads the place that the view of objects in the 

 immediate vicinity is cut off; which would never 

 happen unless numerous particles were massed in 

 a small space. Yet no period is more free from 2 

 wind than a period of cloud. Add now a con 

 sideration of an opposite character : When the sun 

 rarefies at his rising the thick dank morning air, 



