300 HISTORY OF 



marks a peculiar lightness in the air, it is no 

 wonder that it foretells a storm. 



The winds, upon large waters, are generally 

 more regular than those upon land. The wind at 

 sea generally blows with an even steady gale ; 

 the wind at land puffs by intervals, increasing its 

 strength, and remitting it, without any apparent 

 cause. This, in a great measure, may be owing 

 to the many mountains, towers, or trees, that it 

 meets in its way, all contributing either to turn 

 it from its course, or interrupt its passage. 



The east wind blows more constantly than any 

 other, and for an obvious reason : all other winds 

 are, in some measure, deviations from it, and partly 

 may owe their origin thereto. It is generally, like- 

 wise, the most powerful, and for the same reason. 



There are often double currents of the air. 

 While the wind blows one way, we frequently see 

 the clouds move another. This is generally the 

 case before thunder ; for it is well known that the 

 thunder cloud always moves against the wind : 

 the cause of this surprising appearance has hither- 

 to remained a secret. From hence we may con- 

 clude, that weathercocks only inform us of that 

 current of the air which is near the surface of 

 the earth, but are often erroneous with regard 

 to the upper regions ; and, in fact, Derham has 

 often found them erroneous. 



Winds are generally more powerful on elevated 

 situations than on the plain, because their pro- 

 gress is interrupted by fewer obstacles. In pro- 

 portion as we ascend the heights of a mountain, 

 the violence of the weather seems to increase, 



