Tubby offered no opinion for a few seconds, but his ordinarily round and smiling face grew grave.  A sudden apprehension had flashed into his mind.

“Tell me, Merritt,” he said, “can you see any other lights?”

“No,” replied Merritt, after peering with half closed eyes at the white light.

“I can,” suddenly shouted young Hiram.

“You can?”

“Yes; some distance below the white light I can see a green one to the right and a red one on the left.”

“Shades of Father Neptune!” groaned Tubby.  “It’s just as I thought, Merritt—­that light yonder is a steamer’s mast lantern, and the fact that Hiram can see both her port and starboard lamps beneath shows that she’s coming right for us.”

This was alarming enough.  Without lanterns, without the means of making any noise sufficiently loud to attract the attention of those on the approaching vessel, the occupants of the Plying Fish were in about as serious a predicament as one could imagine.  To make matters worse, the wind began to drop and come in puffs which only urged the Flying Fish ahead slowly.  Tubby made a rapid mental calculation, and decided that hardly anything short of a miracle could save them from being run down, unless the steamer saw them and changed her course.

“Can’t we shout and make them hear us?” asked Hiram in an alarmed voice.  He saw from the troubled faces of both the elder lads that something serious indeed was the matter.

“We might try it,” responded Tubby, with a bitter shrug.  “But it’s about as much use as a mouth organ in a symphony orchestra would be.  Better get on the life belts.”

With hands that trembled with the sense of impending disaster, the three boys strapped on the cork jackets.

“Now all shout together,” said Merritt, when this was done.

Standing erect, the three young castaways placed their hands funnel-wise to their mouths and roared out together: 

“Ship ahoy!  St-eam-er a-hoy!”

They were alarmed and not ashamed to admit it.

“No good,” said Tubby, after they had roared themselves hoarse.  “When she strikes us, jump over the starboard bow and dive as deep as you can.  If you don’t, the propellers are liable to catch us.”

It was a grim prospect, and no wonder the boys grew white and their faces strained as the impending peril bore down on them.

They could now see that she was a large vessel—­a liner, to judge from the rows of lighted portholes on her steep black sides.  Her bow lights gleamed like the eye of some monster intent on devouring the Flying Fish and her occupants.  On and on she came.  The air trembled with the vibration of her mighty engines, and a great white “’bone” foamed up at her sharp prow.

Not one of the boys spoke as the vessel came nearer and nearer, although it speedily grew evident that unless a wind sprang up or the lookout saw them, it was inevitable that they would be cut in two amidships.