knowing what
you cannot know. You can only guess about new things, which you have
never seen before, by comparing them with old things, which you have seen
before; and you had seen flowers, and snakes, and fishes' backbones, and
made a very fair guess from them. After all, some of these stalked star-
fish are so like flowers, lilies especially, that they are called
Encrinites; and the whole family is called Crinoids, or lily-like
creatures, from the Greek work _krinon_, a lily; and as for corals and
corallines, learned men, in spite of all their care and shrewdness, made
mistake after mistake about them, which they had to correct again and
again, till now, I trust, they have got at something very like the truth.
No, I shall only call you silly if you do what some little boys are apt
to do--call other boys, and, still worse, servants or poor people, silly
for not knowing what they cannot know.

But are not poor people often very silly about animals and plants? The
boys at the village school say that slowworms are poisonous; is not that
silly?

Not at all. They know that adders bite, and so they think that slowworms
bite too. They are wrong; and they must be told that they are wrong, and
scolded if they kill a slowworm. But silly they are not.

But is it not silly to fancy that swallows sleep all the winter at the
bottom of the pond?

I do not think so. The boys cannot know where the swallows go; and if
you told them--what is true--that the swallows find their way every
autumn through France, through Spain, over the Straits of Gibraltar, into
Morocco, and some, I believe, over the great desert of Zahara into
Negroland: and if you told them--what is true also--that the young
swallows actually find their way into Africa without having been along
the road before; because the old swallows go south a week or two first,
and leave the young ones to guess out the way for themselves: if you told
them that, then they would have a right to say, "Do you expect us to
believe that? That is much more wonderful than that the swallows should
sleep in the pond."

But is it?

Yes; to them. They know that bats and dormice and other things sleep all
the winter; so why should not swallows sleep? They see the swallows
about the water, and often dipping almost into it. They know that fishes
live under water, and that many insects--like May-flies and caddis-flies
and water-beetles--live sometimes in the water, sometimes in the o