“What a magnificent ‘sun-spot!’” exclaimed the professor in a tone of admiration.  “Just take a peep at it.”

I placed my eye to the telescope, and saw the glowing surface of the disc resolved into a marvellous web of shining patches on a dimmer background, and in the midst a large blotch which reminded me of a quarry hole as delineated on the plan of a surveyor.

“Have you been able to throw any fresh light on these mysterious ‘spots?’” I enquired.

“I am more than ever persuaded they are breaks in the photosphere caused by eruptions of heated matter, chiefly gaseous from the interior—­eruptions such as might give rise to craters like that of Womla, or those of the moon, were the sun cooler.  No doubt that eminent authority, Professor Sylvanus Pettifer Possil, regards them as aerial hurricanes; but the more I see, the more I am constrained to regard Sylvanus Pettifer Possil as a silly vain asteroid.”

While Gazen was yet speaking we both became sensible of an unwonted stillness in the car.

The machinery had ceased to vibrate.

Our feelings at this discovery were akin to those of passengers in an ocean steamer when the screw stops—­a welcome relief to the monotony of the voyage, a vague apprehension of danger, and curiosity to learn what had happened.

“Is there anything wrong, Carmichael?” asked Gazen through the speaking tube.

There was no response.

“I say, Carmichael, is anything the matter?” he reiterated in a louder tone.

Still no answer.

We were now thoroughly alarmed, and though it was against the rules, we descended into the machinery room.  The cause of Carmichael’s silence was only too apparent.  We saw him lying on the floor beside his strange machine, with his head leaning against the wall.  There was a placid expression on his face, and he appeared to slumber; but we soon found that he was either in a faint or dead.  Without loss of time we tried the first simple restoratives at hand, but they proved of no avail.

Gazen went and called Miss Carmichael.

She had been resting in her cabin after her trying experience with the dragon, and although most anxious about her father, and far from well herself, she behaved with calm self-possession.

“I think the heat has overcome him,” she said, after a quick examination; and truly the cabin was insufferably hot, thanks to the machinery and the fervid rays of the sun.

We could not open the scuttles and admit fresh air, for there was little or none to admit.

“I shall try oxygen,” she said on reflecting a moment.

Accordingly, while Gazen, in obedience to her directions began to work Carmichael’s arms up and down, after the method of artificial respiration which had brought me round at the outset of our journey, she and I administered oxygen gas from one of our steel bottles to his lungs by means of a makeshift funnel applied to his mouth.  In some fifteen or twenty minutes he began to show signs of returning animation, and soon afterwards, to our great relief, he opened his eyes.