Adela," she called, "here is a good place;" for the little old lady was
still too much shaken up to make much attempt at travelling, so Polly
had begged Mother Fisher and Grandpapa to ask Adela to come with them
on their sightseeing trips.

And this was done, and the young girl was happy as a bird. So here she
was, going down to Marken too.

Adela ran and kneeled down on the seat by Polly's side and hung over
the rail too. "Don't the houses lean over queerly?" she said, pointing
to the long narrow buildings they were leaving behind. They look worse
from the water than when we are in the midst of them."

"It's just as if they were holding each other up," said Polly. "Dear
me, I should think they'd tumble over some fine day.

"What makes them sag so?" asked Adela, intently regarding them.

"That's because the city is built on piles, I suppose," said Jasper.
It's mostly sand in Holland, you know, particularly around Amsterdam,
and so they had to drive down piles to get something strong enough to
put their houses on. That's what--who was it?--oh I know--Erasmus--meant
when he said, 'I know a city whose inhabitants dwell on the tops of the
trees like rooks.'"

"O dear me," said Adela, quite impressed; "well, what makes them not
sag any more?" she asked at length.

"Because they've sagged all they want to, I suppose'" said Jasper,
laughing. "Anyway they've stood so for years on years--probably, so