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stanlially a gangrene of the cellular system of the plant, or rather of its 
tuber; the starchy part being at first gnerally unaffected by the disease. 
Certain atmospheric conditions or states may be more or less favorable- 
to the development and propagation of the disease where it already exists, 
as certain other of its conditions or states may tend to check the progress 4 
of it in its different stages of advancement. These conditions or states 
of the atmosphere may even predispose some plants and animals to cer¬ 
tain forms of disease, but they cannot be said to cause the disease itself. 
Meteorologists, in their investigations of the atmosphere, have confined 
themselves mainly to its mechanical properties, and to the various visible 
phenomena within its apparent limits. They have ascertained its weight, 
its height, its decrements of heat and pressure, its power over the solar 
rays, its evaporation, absorption, &c.; but its life-giving properties, its 
power over organic substances, its agency in supporting the animal and 
vegetable tissues, have as yet hardly attracted their notice. They have 1 
never looked upon it in the light of an immense life-giving continent, as it 
is, incessantly acting upon the substances of the enclosed dead continent 
with a view to vital development. They have ascertained the startling 
fact that a man of ordinary stature, sustains the enormous sum of thirty- 
two thousand pounds of atmospheric pressure; but its office in vitalizing 
the material world, and clothing it in its thousand diversified and beauti- 
fully variegated forms of life, has been a subject of comparatively little 
moment. Instead of being impregnated with the seeds of death, it is 
eternally vivifying the earth and fertilizing its particles of matter ; ob¬ 
serving an uniform course and apparently obeying an intrinsic law. It is 
not a principle of destruction, of elementary dissolution; but, under the 
Divine economy, a 'principle of life. It brings down from heaven the 
balmy spring, the dews, and the rain and the life-giving sunshine. It is 
thus beautifully described by the great poet and true meteorologist of 
antiquity:— 
“Turn pater omnipotcns fcecundis imhribi.s aether 
Congugis in greminon laet.ie descend it, et omnes 
Magnus aiit, magno commixtus corpore, foetus.” 
Thus representing the ‘almighty father Aether' (or the atmosphere) as 
descending into the bosom of his joyous spouse in fructifying showers, 
and great himself, mingling with her great body, and quickening all 
things into life. We can conceive of nothing more beautiful or significaah- 
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