Next morning Tom set to work at once to explore the Blue Lake. First he made a map of that part of the country. Then he drew a straight line from McDonald Bay to the Lake, then marked it straight across to the opposite end of the Lake. This done, he made a sounding line of a long rope with heavy lead tied at the end, and leaning over the edge of the bank he tried banging his line against the place where he hoped the opening might be. Many times he struck with his leaded line, but each time it hit against the bank. Tom sighed sadly, thinking that if only he lived in England instead of in Australia, there would come a little fairy, most likely the Queen of the Fairies herself, and she would take him down into the water and show him the hidden openings and other wonders. But Australia was a new country, and very few people here believed there were fairies anywhere.
Just as Tom had sadly given up all hope of fairy aid, he felt the line pulled gently, oh so gently at first, then harder and harder, until at last he could scarcely hold it in his hands.
“I won’t give up,” thought Tom, “the worst that can happen if I fall in is a wetting. I can easily swim out.”
He held on and was gradually drawn down beneath the water; deeper and deeper he went, until at last he was jerked on one side, and found himself on the bank of a fiercely rushing torrent.
Tom’s first thought was one of triumph. “I knew it was an underground river,” he cried aloud. He jumped around as if a pistol shot had been fired, when a voice near by said, “The least you might do is to thank me for bringing you here.” There stood a tiny gnome dressed all in green. “I pulled the leaded line that you threw down into the water, and I must say that for a boy who has the sense to try and find the opening of the river, you know very little about your country. Australia a new country indeed? It was thousands of years old before Britain was in existence. Oh, I know what I’m talking about, for I have lived underground for a good many hundred years.”
Tom was so thoroughly surprised that he stood quite still, and stared at the little gnome, who continued: “No fairies either? Oh indeed, I could tell a different story. No one to help the poor little Australians? The helpers are here right enough, but most little Australians not only don’t want the help of the gnomes and fairies, but don’t believe there are such beings anywhere. Why, even the one I have just helped has not a word of thanks for what I have done for him.”
“Oh, I do thank you, how much I can’t say; I wanted to prove that the Blue Lake is a river, yes, I wanted to prove that more than anything else in the world, and I am so glad you have let me come to see it. Please may I explore some more of the river?”
Not only did the kind gnome allow Tom to see the wonders underground, but he offered to act as guide. As soon as Tom had eaten a bunch of wild cherries that the gnome gave him, he was not only dry and comfortable, but had become as small as the gnome, and could understand the talk of bird, beast and fish.
Tom was surprised at the great change, and told the gnome he had often enough eaten wild cherries before, and nothing strange had taken place; but the gnome explained that only cherries picked by a gnome, and by him given to a human being, had the power to so change the one who ate them.
“Now,” said the gnome, “you shall see the source of this underground river. It would take rather long to get there by walking, so we shall go on my airship.”