276 NATURAL HISTORY 



already inquired of the local beginnings; and of those winds 

 which have their beginning of motion in their first impul 

 sion, as in those which are cast down from above or blow 

 out of the earth, the raising of their motion is manifest : 

 others descend below their own beginnings ; others ascend, 

 and being resisted by the air, become voluminous, espe 

 cially near the angles of their violence ; but of those which 

 are engendered every where in this inferior air (which are 

 the frequentest of all the winds), the inquisition seems to 

 be somewhat obscure, although it be a vulgar thing, as we 

 have set down in the commentation under the eighth article. 



2. We found likewise an image or representation of this 

 in that close tower which we spake of before ; for we varied 

 that trial three ways. The first was that which we spake 

 of before ; namely, a fire of clear burning coals. The second 

 was a kettle of seething water, the fire being set away, and 

 then the motion of the cross of feathers was more slow and 

 dull. The third was with both fire and kettle ; and then 

 the agitation of the cross of feathers was very vehement, 

 so that sometimes it would whirl up and down, as if it had 

 been in a petty whirlwind, the water yielding store of va 

 pours, and the fire which stood by it dissipating and dis 

 persing them. 



3. So that the chief cause of exciting motion in the winds 

 is the overcharging of the air by a new addition of air 

 engendered by vapours. Now we must see concerning the 

 direction of the motion, and of the whirling, which is a 

 change of the direction. 



4. The nurseries and food of the winds doth govern their 

 progressive motion ; which nurseries and feedings are like 

 unto the springs of rivers ; namely, the places where there 

 are great store of vapours, for there is the native country of 

 the winds. Then when they have found a current, where 

 the air makes no resistance (as water when it finds a falling 

 way), then whatsoever semblable matter they find by the 

 way, they take into their fellowship, and mix it with their 

 currents even as rivers do. So that the winds blow always 

 from that side where their nurseries are which feed them. 



5. Where there are no notable nurseries in any certain 

 place, the winds stray very much, and do easily change 

 their current, as in the middle of the sea, and large spacious 

 fields. 



6. Where there are great nurseries of the winds in one 

 place, but in the way of its progress it hath but small ad 

 ditions, there the winds blow strongly in their beginnings, 





