“What!”

“Yes. He paid to be set ashore at Cherbourg.”

“Did he say where he was going?”

“Not a word.”

Frank returned to his friends and told them the news.

It was very exasperating, but the detective said:

“Let’s cross the bay of the Seine and inquire about him. We may get on his trail yet.”

This plan was carried out.

In a short time afterwards the aerostat landed near the city, and Frank left her again.

He soon came hastening back, his face aglow with pleasure, and cried, as he got aboard: