water. We have seen it drawn up by the fairy "heat," invisible
into the sky; there fairy "cohesion" seized it and formed it into
water-drops and the giant, "gravitation," pulled it down again to
the earth. Or, if it rose to freezing regions, the fairy of
"crystallization" built it up into snow-crystals, again to fall
to the earth, and either to be melted back into water by heat, or
to slide down the valleys by force of gravitation, till it became
squeezed into ice. We have detected it, when invisible, forming a
veil round our earth, and keeping off the intense heat of the
sun's rays by day, or shutting it in by night. We have seen it
chilled by the blades of grass, forming sparkling dew-drops or
crystals of hoar-frost, glistening in the early morning sun; and
we have seen it in the dark underground, being drunk up greedily
by the roots of plants. We have started with it from the tropics,
and travelled over land and sea, watching it forming rivers, or
flowing underground in springs, or moving onwards to the high
mountains or the poles, and coming back again in glaciers and
icebergs. Through all this, while it is being carried
hither and thither by invisible power, we find no trace of its
becoming worn out, or likely to rest from its labours. Ever
onwards it goes, up and down, and round and round the world,
taking many forms, and performing many wonderful feats. We have
seen some of the work that it does, in refreshing the air,
feeding the plants, giving us clear, sparkling water to drink,
and carrying matter to the sea; but besides this, it does a
wonderful work in altering all the face of our earth. This work
we shall consider in the next lecture, on "The two great
Sculptors - Water and Ice."