“Gone!” echoed the inventor, in startled tones.

“Blowed up—smashed into a thousand pieces!”

“Good heavens! How did it happen?”

“Yer see, ther naygur an’ I left her a few moments afther you wint, an’ there suddenly sounded a terrible explosion insoide av her. Ther next moment she wuz a wreck.”

“What caused the explosion?”

“A can av that terrible powder, I’m thinkin’, wid which you do be afther loadin’ ther bullets we used in ther guns. It shtood on the edge av a shelf, an’ must have fell to ther flure.”

As there was no means of ascertaining positively what caused the explosion, and Barney’s idea was the most plausible, Frank was forced to accept this theory.

He was, in fact, right in his conclusion.

They returned to where they had left the machine and found a big crowd on the scene, attracted there by the violent report.

As the engine of the clouds was completely destroyed, they could do nothing with the remains, and therefore left them.