. "What keeps the powder dry?"

"We have water-proof charges prepared."

"But how can you fire them under the water?" persisted Eric.

"By electricity," responded Mr. Lacelle. "A report of blasting rock a
little distance off, will scarcely disturb us upon the land; but under the
water it is very different. We were once blasting rocks near the coast,
and another party were at work three quarters of a mile from us.

"Our charge was set, and ready to go off; I sent word to our distant
neighbors that we were about to blast, and they had better come up until
it was over. My courtesy was repaid by a very profane answer, accompanied
with a request to 'blast away.'

"So the charge was set off; and the unfortunate divers in the distance
were hauled out of the water more dead than alive. I afterwards learned
from them that the shock was tremendous."

"When you blow up the rocks, do you place the charges under them?"
inquired Eric.

"O, no; that would have no effect: holes are drilled in the rock, and the
charges placed within them."

"And when the rocks are blown, what do you do with the pieces that come
off?" asked Eric.

"We grapple them with hooks and chains, and draw them to the surface."

"It is very interesting, and I am very much obliged to you for telling me
so much," said Eric. "I wish I could learn _all_ about it."

"Well, my boy, you shall go with me to-morrow; and, if you're not afraid
to venture, I'll take you down beneath the sea with me. It is quite safe
near Amsterdam."

"O, thank you, sir," said Eric, eagerly, grasping the kind Frenchman's
hand.

"I must go now to the palace," said Mr. Lacelle. "I have an engagement
there. Will you do me the honor to amuse yourself here until I return?"

"Thank you," said Eric again, with a joyous smile; for Mr. Lacelle's room
was stored with 'curios' from the bottom of the sea, and Eric knew he
could spend a long time very comfortably there.

He was careful to secure Froll in her cage, that she might do no mischief;
and then he had a thoroughly good time, examining the sea things; and as
they were all labelled with name and date, and the place from which they
were taken, he gained much useful information.

Before night a letter came from his uncle, saying that Johnny was quite
ill, and had been unable to travel to the Hague; but he was now so much
better, that they would probably join Eric in a day or two.

"I shan't mind waiting," said Eric to himself; "and