myself, "If that stream had been a little, only a little stronger, or if
the rock above it had been only a little weaker, it would have been no
laughing matter then; the village might have been shaken to the ground;
the rocks hurled into the torrent; jets of steam and of hot water, mixed,
it may be, with deadly gases, have roared out of the riven ground; that
might have happened here, in short, which has happened and happens still
in a hundred places in the world, whenever the rocks are too weak to
stand the pressure of the steam below, and the solid earth bursts as an
engine boiler bursts when the steam within it is too strong." And when
those thoughts came into my mind, I was in no humour to jest any more
about "young earthquakes," or "Madam How's boilers;" but rather to say
with the wise man of old, "It is of the Lord's mercies that we are not
consumed."

Most strange, most terrible also, are the tricks which this underground
steam plays. It will make the ground, which seems to us so hard and
firm, roll and rock in waves, till people are sea-sick, as on board a
ship; and that rocking motion (which is the most common) will often, when
it is but slight, set the bells ringing in the steeples, or make the
furniture, and things on shelves, jump about quaintly enough. It will
make trees bend to and fro, as if a wind was blowing through them; open
doors suddenly, and shut them again with a slam; make the timbers of the
floors and roofs creak, as they do in a ship at sea; or give men such
frights as one of the dock-keepers at Liverpool got in the earthquake in
1863, when his watchbox rocked so, that he thought some one was going to
pitch him over into the dock. But these are only little hints and
warnings of what it can do. When it is strong enough, it will rock down
houses and churches into heaps of ruins, or, if it leaves them standing,
crack them from top to bottom, so that they must be pulled down and
rebuilt.