CAUSES OF BLIZZARDS. 131 



the settlements into the wilderness, it is more easy 

 to run to shelter than formerly, when there were 

 thousands of square miles without a house or even a 

 bush of any kind, to be seen upon them. 



Now, as regards the cause of blizzards, it seems 

 hard to come to any other conclusion than that the 

 sudden onset of the intense cold, which characterizes 

 these terrible visitations, is due to atmospheric disturb- 

 ances taking place in the great celestial alti- 

 tudes, far beyond the reach of human observation: 

 which cause a strata of icy wind, there prevailing, 

 to descend upon the earth. This seems to afford the 

 only reasonable way of accounting for their sudden 

 occurrence perhaps during the course of a mild day, 

 after a spell of fine and apparently settled weather. 



That currents of air blowing in different directions 

 at the same time do exist, we can often see for our- 

 selves, by observing the movements of the clouds, 

 which may be seen passing in different directions, 

 at different altitudes, thereby placing this fact beyond 

 a doubt. Also, the approach of a storm is often 

 indicated by the clouds flying rapidly overhead, 

 while a calm still prevails at the earth's surface: thus 

 proving that a gale, as yet unfelt on earth, is blow- 

 ing in the regions of space above. Then, we know 

 that as we ascend to great elevations we always 

 encounter progressively increasing cold, as we mount 

 up. This is a fact so well established, that it is merely 

 necessary to point it out the occurrence of snow- 

 capped mountain peaks under the rays of a tropical 

 sun, however, affords conclusive proof of it; and 

 observations show that at an altitude of about 16,000 



