DEW OF THE BREATH. 203 



against which it is breathed. In dry and warm 

 states of the atmosphere, that dew is not obser- 

 vable, though even then the breath will stain a 

 mirror, if held near ; but when the atmosphere is 

 cold or moist, the breath of man, and of all the 

 warm blooded animals, becomes visible; and in 

 keen frosts, a man's own breath will cover his 

 hair with hoar frost, and even form ice upon his 

 face. But the same heated moisture of the 

 breath which becomes apparent in those cases, 

 exists in every case, whether circumstances render 

 it visible or not, and thus it becomes a protection 

 against draughts or currents of air. These blow 

 the warm and moist breath against the face ; and 

 that, instead of parching it, as the common air 

 would do, dews gently upon it, and protects it 

 from injury. The effect is much greater than one 

 would suppose, for if one stand with the head 

 bare when the wind blows keenly, one can bear it 

 longest by facing it. It is not a little curious, 

 that the danger of catching cold should, like all 

 other dangers, be greatly diminished by being faced. 

 The mists, or dews, which are formed in the 

 higher regions of the atmosphere, are of a very 

 different character from those that are formed on 

 or near the surface of the earth. The earth mist, 

 as we may call the lower one, before it can rise 

 upward in the air, and disturb the state of things 

 there, has the resistance both of gravitation and 

 cohesion to overcome ; whereas, the descent of a 

 mist or cloud, formed in the upper part of the 

 sky, has both of those resistances as powers acting 

 in favour of its descent. That consideration helps to 

 explain so many of the phenomena of the weather 

 phenomena which are very important for the triple 

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