For an instant after the electrical charge had been fired nothing seem to happen. The giant starfish still enveloped Ned Newton in its grip, while Tom and his two companions stood tensely waiting and those in the submarine looked anxiously out through the thick glass windows.

Then, as the powerful current made itself felt, those watching saw one of the arms slowly loosen its grip. Another floated upward, as a strand of rope idly drifts in the current. Tom saw this, and called through his telephone:

"He's feeling it! Go to him, boys! Koku, you with the axe!"

They needed no second urging.

Springing toward the monster, Koku with upraised axe and Norton with the lance, they attacked the starfish. Hacking and stabbing, they completed the work begun by Tom's electric gun. With one powerful stroke, even hampered as he was by the heavy medium in which he operated, Koku lopped off one of the legs. Norton thrust his lance deep into the body of the monster, but this was hardly needed, for the starfish was now dead, and gradually the remaining arms relaxed their hold.

Pushing with their weapons, the giant and the sailor now freed Ned from the bulk of the creature, which floated away. It was almost immediately attacked by a school of fish that seemed to have been waiting for just this chance. Ned Newton was freed, but for a moment he staggered about on the floor of the sea, hardly able to stand.

"Are you all right, Ned? Did he pierce your suit?" asked Tom, anxiously through the telephone.

"Yes, I'm all right," came back the reassuring answer. "I'm a bit cramped from the way he held me, but that's all. Guess he found this suit of rubber and steel too much for his digestion."

Slowly, for Ned was indeed a bit stiff and cramped, they made their way back to the submarine, passing through a vast horde of small fishes which had been attracted by the dismemberment of the monster that had been killed.

"There'll be sharks along soon," said Tom to Ned through the telephone. "They're not going to miss such a gathering of food as these small fry present. And sharks will present a different emergency from starfish."

Tom spoke truly, for a little later, when they were all once more safely within the submarine, looking through the windows, they saw a school of hungry sharks feeding on the millions of small fish that gathered to eat the creature that had attacked Ned.

"What did you think was happening to you out there?" asked Tom, when the diving suits had been put away.

"I didn't know what to think," was the answer. "I was prospecting around, and I leaned over to pick up a particularly beautiful bit of coral. All at once I felt something over me, as a cloud sometimes hides the sun. I looked up, saw a big black shape settling down, and then I felt my arms pinned to my sides. At first I thought it was an octopus, but in a moment I realized what it was. Though I never thought before that starfish grew so large."

"Nor I," added Tom. "Well, you've had an experience, to say the least."

They remained a little longer in the vicinity, Tom and his officers making observations they thought would be useful to them later, and then the submarine went up to the surface.

They cruised in the open the rest of that day, recharging the storage batteries and getting ready for the search which, Tom calculated, would take them some time. As he had explained, it would not be easy to locate the Pandora in the fathomless depths of the sea.

Ned and Mr. Damon did some fishing while they were on the surface, and, as their luck was good, there was a welcome change from the usual food of the M. N. 1. Though, as Tom had installed a refrigerating plant, fresh meat could be kept for some time, and this, in addition to the tinned and preserved foods, gave them an ample larder.

"When are we going to begin the real search for the gold?" asked Mr. Hardley that evening.

"I should say in another day or two," Tom answered, after he had consulted the charts and made calculations of their progress since leaving their dock. "We shall then be in the vicinity of the place where you say the Pandora went down, and, if you are sure of your location, we ought to be able to come approximately near to the location of the gold wreck."

"Of course I am sure of my figures," declared Mr. Hardley. "I had them directly from the first mate, who gave them to the captain."

"Well, it remains to be seen," replied Tom Swift. "We'll know in a few days."

"And I hope there will be no more taking chances," went on the gold-seeker. "I don't see any sense in you people going out in diving suits to fight starfish. We need those suits to recover the gold with, and it's foolish to take needless risks."

His tone and manner were dictatorial, but Tom said nothing. Only when he and Mr. Damon were alone a little later the eccentric man said:

"Tom will you ever forgive me for introducing you to such a pest?"

"Oh, well, you didn't know what he was," said Tom good- naturedly. "You're as badly taken in as I am. Once we get the gold and give him his share, he can get off my boat. I'll have nothing more to do with him!"

Not wishing to navigate in the darkness, for fear of not being able to keep an accurate record of the course and the distance made Tom submerged the craft when night came and let her come to rest on the bottom of the sea. He calculated that two days later they would be in the vicinity of the Pandora.

The night passed without incident, situated, as they were, on the sand about three hundred feet below the surface; and after breakfast Tom announced that they would go up and head directly for the place where the Pandora had foundered.

The ballast tanks were emptied, the rising rudder set, and the M. N. 1 began to ascend. She was still several fathoms from the surface when all on board became aware of a violent pitching and tossing motion.

"Bless my postage stamp, Tom!" exclaimed Mr. Damon, "what's the matter now?"

"Has anything gone wrong?" demanded Mr. Hardley.

"Nothing, except that we are coming up into a storm," answered the young inventor. "The wind is blowing hard up above and the waves are high. The swell makes itself felt even down here."

Tom's explanation of the cause of the pitching and rolling of the submarine proved correct. When they reached the surface and an observation was taken from the conning tower, it was seen that a terrific storm was raging. It was out of the question to open the hatches, or the M. N. 1 would have been swamped. The waves were high, it was raining hard and the wind blowing a hurricane.

"Well, here's where we demonstrate the advantage of traveling in a submarine," announced Tom, when it was seen that journeying on the surface was out of the question. "The disturbance does not go far below the top. We'll submerge and be in quiet waters."

He gave the orders, and soon the craft was sinking again. The deeper she went the more untroubled the sea became, until, when half way to the bottom, there was no vestige of the storm.

"Are we going to lie here on the bottom all day, or make some progress toward our destination?" asked the gold-seeker, when Tom came into the main cabin after a visit to the engine room. "It seems to me," went on Mr. Hardley, "that we've wasted enough time! I'd like to get to the wreck, and begin taking out the gold."

"That is my plan," said Tom quietly. "We will proceed presently--just as soon as navigating calculations can be made and checked up. If we travel under water we want to go in the right direction."

His manner toward the gold-seeker was cool and distant. It was easy to see that relations were strained. But Tom would fulfill his part of the contract.

A little later, after having floated quietly for half an hour or so, the craft was put in motion, traveling under water by means of her electric motors. All that day she surged on through the salty sea, no more disturbed by the storm above than was some mollusk on the sandy bottom.

It was toward evening, as they could tell by the clocks and not by any change in daylight or darkness, that, as the submarine traveled on, there came a sudden violent concussion.

"What's that?" cried Mr. Damon.

"We've struck something!" replied Tom, who was with the others in the cabin, the navigation of the craft having been entrusted to one of the officers. "Keep cool, there's no danger!"

"Perhaps we have struck the wreck!" exclaimed Mr. Hardley.

"We aren't near her," answered the young inventor. "But it may be some other half-submerged derelict. I'll go to see, and--"

Tom's words were choked off by a sudden swirl of the craft. She seemed about to turn completely over, and then, twisted to an uncomfortable angle, so that those within her slid to the side walls of the cabin, the M. N. 1 came to an abrupt stop. At the same time she seemed to vibrate and tremble as if in terror of some unknown fate.

"Something has gone wrong!" exclaimed Tom, and he hurried to the engine room, walking, as best he could with the craft at that grotesque angle. The others followed him.

"What's the matter, Earle?" asked Tom of his chief assistant.

"One of the rudders has broken, sir," was the answer. "It's thrown us off our even keel. I'll start the gyroscope, and that ought to stabilize us."

"The gyroscope!" cried Tom. "I didn't bring it. I didn't think we'd need it!"

For a moment Earle looked at his commander. Then he said:

"Well, perhaps we can make a shift if we can repair the broken rudder. We must have struck a powerful cross current, or maybe a whirlpool, that tore the main rudder loose. We've rammed a sand bank, or stuck her nose into the bottom in some shallow place, I'm afraid. We can't go ahead or back up."

"Do you mean we're stuck, as we were in the mud bank?" asked Mr. Hardley.

"Yes," answered Tom, and Earle nodded to confirm that version of it.

"But we'll get out!" declared Tom. "This is only a slight accident. It doesn't amount to anything, though I'm sorry now I didn't take my father's advice and bring the gyroscope rudder along. It would have acted automatically to have prevented this. Now, Mr. Earle, we'll see what's to be done."

All night long they worked, but when morning came, as told by the clocks, they were still in jeopardy.

And then a new peril confronted them!

Earle, coming from the crew's quarters, spoke to Tom quietly in the main cabin.

"We'll have to turn on one of the auxiliary air tanks," he said. "We've consumed more than the usual amount on account of the men working so hard, and we used one of the compressed air motors to aid the electrics. We'll have to open up the reserve tank."

"Very well, do so," ordered Tom.

But a grim look came to his face when Earle, returning a little later, reported with blanched cheeks:

"The extra tank hasn't an atom of air in it, sir!"

"What do you mean?" asked Tom, in fear and alarm.

"I mean that the valve has been opened in some way--broken perhaps by accident--and all the air we have is what's in the submarine now. Not an atom in reserve, sir!"

"Whew!" whistled Tom, and then he stood up and began breathing quickly.

Already the atmosphere was beginning to be tainted, as it always becomes in a closed place when no fresh oxygen can enter. Without more fresh air the lives of all in the submarine were in imminent peril. And even as Tom listened to the report of his officer, he and the others began gasping for breath.