"It was all that wretched young Shadow's fault!" roared Emu Bill.
"But you were there first, Bill," remonstrated Mackay, laughingly.
"Of course we were. We went plump into the filthy boilers; but we got a good grip o' the sides, and were sliding out quick an' lively, when, blow me! if that howlin' scarecrow didn't bounce down on top o' us, an' sent us swimmin' like tadpoles to the bottom. Ugh!"
But their indignation quelled speedily when they learnt how excellent had been the intentions of the much-maligned youth.
"It must be a hot spring," said Bob.
"And there are more of them," cried Jack. "See, they are scattered all round the foot of the mountain."
"I reckon it is hot, right enough," grumbled Emu Bill. "I'm just 'bout turned into a Salamander, I is."
As Jack had noticed, quite a number of similar indentations formed a line right along the base of the mountain, and in each yawning crater examined, a greenish-yellow fluid bubbled tempestuously. High overhead the smoke-wreaths dissembled into thin air, and for a brief space all was beautifully clear. Then a dull rumble like the mutterings of subdued thunder was heard, and immediately snowy puffs of smoke issued from the strange cavities. The denser fumes rapidly spread along the ground like a turbulent, foaming sea; then the whole seemed gradually to rise upwards and suspend as a filmy pall before the face of the mountain. Yet, strangely enough, the noxious odours were now almost absent.
"Ay, it's vera marvellous," said Mackay, with a sigh. "So does Nature protect her treasure-houses."
"It's a wonder you managed to get through without accident when you came," Bob observed thoughtfully. "But, then, it's possible the line was clear when you passed."