The boat was lifted up and down for seventy-two locks. Erik never tired of watching the lock gates opening and closing.
THE LOCK AT TROLLHÄTTAN, ON THE GÖTA CANAL
Frequently the boat would stop to take on passengers and freight. At these times, Erik and Johan would jump off and wander about the countryside. It was upon one of these excursions that something happened to them.
They had been passing medieval castles along the route. Among them was Bohus, once a powerful stronghold, whose two ruined towers are now called Father's Hat and Mother's Cap.
Another was Läcko (lĕck´ō) Castle, which sits upon Lake Väner (vĕ´nẽr), the largest lake in Europe, except for those in Russia. Erik was charmed with Läcko's fierce mystery.
But as the great bulk of Vadstena (vaud´stān-ȧ) Castle came into view across Lake Vätter (vĕt´tẽr), Erik felt a thrill of pride. He could hardly wait to visit it.
Whenever the boys left the boat, Fru Banker cautioned them to remember to return in time. For, should they be late, the boat would go off without them.
Now, however, as they examined Vadstena Castle, with its ancient moats and ramparts, they forgot this advice. Their minds were filled with pictures of the days when Sweden was at war, when Gustavus Vasa (gŭs tā´vŭs vä´sȧ), who built it, gained independence for the Swedish people.
