90 
HAROLD’S DISCUSSIONS. 
hence, and there is no need to spend anxious mo¬ 
ments over it. 
We are in the habit of thinking of the earth with¬ 
out its atmosphere, but it is truly a part of our globe. 
It is quite as necessary to life on the earth as are the 
rock-sphere and the oceans of water. In a very im¬ 
portant sense we do not live on the earth but in the 
earth—i. e., in the atmosphere. All terrestrial life 
would immediately perish if this gaseous envelope 
were removed. 
Not only is life possible in this air-sphere, but its 
well-being depends greatly on the warmth, moisture, 
and movements of that sphere. Man’s prosperity 
and happiness are so dependent upon the conditions 
of the atmosphere that where these are most favor¬ 
able he attains his highest civilization. 
Atmospheric conditions taken together for a pe¬ 
riod of time constitute climate. In the temperate 
zone climate consists of a mixture of wind and clouds, 
sun and frost, dew and snow, warm and cold. All 
these are continually changing and forming new com¬ 
binations. 
Although the atmosphere is so important to the 
life of the globe, it is the last scientific topic that has 
received studious attention. This is probably due to 
the idea that prevails so largely that we can not learn 
much about wind and storm; and this is partly true 
because of the extensive movements of the air, re¬ 
quiring observations at many and widely separated 
points. 
In the year 1870 , the United States Government 
