Oscar tried to free himself but in vain.
Pargloss was a powerful man and could not be made to let go.
In desperation, Oscar pulled the trigger of his pistol.
He scarcely expected the weapon to go off, but it did, and the bullet struck Pargloss in the shoulder.
The man was not seriously injured, but the sudden pain made him loosen his hold and in another instant Oscar was free.
Coming to the surface he reached a ladder running up the side of the lock and soon found himself once more above the canal.
In the meantime, Pargloss' confederate had been made a close prisoner by the others.
"Where is Pargloss?" asked Andy.
"In the canal. Watch for him, he must soon come up."
They did watch, and in a few seconds the criminal appeared and gazed around him savagely.