wide through the dense forest as thoroughly as if a thousand woodmen had been at work there for many years.
When whirlwinds pass from the land to the sea they create waterspouts; of which we shall have something to say in another chapter. Meanwhile, we think it may be interesting to give the following miscellaneous information regarding the atmosphere, gathered from the work of Dr. Buist, who devoted much earnest study to the subject of atmospheric phenomena.
"The weight of the atmosphere is equal to that of a solid globe of lead sixty miles in diameter. Its principal elements are oxygen and nitrogen gases, with a vast quantity of water suspended in them in the shape of vapour; and, commingled with these, a quantity of carbon in the shape of fixed air, sufficient to restore from its mass many-fold the coal that now exists in the world… Water is not compressible or elastic; it may be solidified into ice or vaporized into steam: but the air is elastic and compressible. It may be condensed to any extent by pressure, or expanded to an infinite degree of tenuity by pressure being removed from it. It is not liable to undergo any changes in constitution beyond these, by any of the ordinary influences by which it is affected."
If the heating and cooling process—which we have described as being carried on between the equator and the poles—were to cease, we should
