114 ABOUT THE WEATHER. 



air out above, as may easily be perceived by the motion of 

 the flame of a candle held high up or low down in the 

 door-way. In small things, this is the cause of the 

 draughts so dreaded by the delicate female sex, and even by 

 some delicate gentlemen. In greater matters, it is the 

 cause of that which the mariner, according to circum- 

 stances, prays and whistles for, or curses wind and 

 storm. I shall indeed be answered, that we are none the 

 wiser for this. For when the vernal storm bellows around 

 the bare summit of the Brocken, and whirls the snow up 

 in showery drifts, so that the blinded wanderer, already 

 within a hundred paces of the hospitable house, strays from 

 the path and becomes the prey of death,- the question still 

 remains, where here is the heated room and the opened 

 door ? And after all, the old saying is still true, that he is 

 a wise man who always knows which way the wind blows. 

 I will venture, nevertheless, to point out, that it is by no 

 means so difficult a matter, since the said proverb assumes, 

 that as many winds blow over the earth as there are 

 points on the compass, while in fact, there are really only 

 two winds. 



Meanwhile, before I pass to the explanation of this 

 seemingly strange assertion, I must make mention of 

 another property of the air, not less important in relation 

 to the phenomena which constitute what we call the 

 weather. I allude to a fact well known to every one. 

 When a glass, quite dry, but very cold, is brought into a 

 warm room, it becomes dim, as we say, that is, it becomes 

 suddenly covered with minute drops of water, and this 

 water is so much the more abundantly deposited, the 

 greater the difference between the temperature of the room 

 and that of the glass. Whence comes this water? 

 Certainly not out of the glass, for this was previously 



