Toward night of the second day Birger suddenly announced, "This is Lake Viken, and it is the highest lake on the way between the two ends of the canal route. The captain says that it is more than three hundred feet above the level of the sea."
"Have we seen the prettiest part of the route?" asked Gerda.
"Far from it," was the answer. "The best part of the canal is still
before us, at Trollhättan, although the next lake that we enter, Lake
Vener, is a lovely sheet of water. It is the largest lake in Sweden, and
I must visit one of the lighthouses."
"And I must call upon one of the trolls when we get to Trollhättan," said
Gerda, shaking her head with an air of importance.
"I shall walk up the locks," said Birger.
"You mean that you will walk down the locks," Erik corrected him. "After this the boat will go downstairs until we reach the Göta River."
And when, on the last morning of the journey, they reached Trollhättan, with its famous waterfalls and rapids, the children went ashore and left the boat to walk down the steep hillside by itself, while they ran along beside the canal, or took little trips through the groves to get a better view of the falls. Gerda peered under the trees and bushes for a glimpse of the water witches, but she saw not one.
"And now for your treasures," said Lieutenant Ekman, when they were once more on the boat and it was steaming down the Göta River to Göteborg.
"I bought post-cards," Birger announced, and took a handful from his pocket. "Here are pictures of the giant staircase of locks at Trollhättan, Lake Vener at sunset, the fortress at Karlsborg, the castle at Vettersborg, and the great iron works at Motala."
While Herr Ekman was examining the cards and asking Birger all sorts of questions about them, Gerda was busy spreading out her souvenirs on one of the deck chairs; and such a variety as she had! There was a box of soap, a bag filled with squares of beet-sugar, a tiny hammer made in the shape of the giant steam-hammer "Wrath" at Motala, a package of paper made at one of the great paper-mills, lace collars, a lace cap and some beautiful handkerchiefs from Vadstena.