so engrossed had all been in the question of saving the dolphin that they were unconscious of other things transpiring near them.

all unnoticed, a full-rigged ship had come bearing down upon them from the north.

it had been not a half mile distant when they came to the surface, but they had not looked in that direction or noticed it.

it was now not fifty yards from the dolphin and bearing directly down upon the submarine boat. it looked as if there was a deliberate purpose to run the boat down.

frank reade sprung into the pilot-house and switched the propeller valve, at the same moment turning the rudder sharp about.

the engines responded instantly and the dolphin switched about, not an instant too soon.

the big ship’s hull just grazed her stern. it was certainly a very close call.

24indignantly frank threw open the pilot-house window and shouted:

“ahoy, there, do you mean to run us down?”

only a mumbling reply came back as the ship went on. men were seen in her chains and at her after rail.

the ship lay over to the wind and showed her stern. instinctively all looked for the name.

and before this could be seen, captain hartley, who had been staring at the vessel, cried:

“soul of old neptune! it is the aurelian, mates!”

the announcement was like a dynamite bomb to the others.

“the aurelian!” gasped clifford.

“are you sure of it?” cried frank, eagerly.

“of course i am; don’t you suppose i would know my own ship in any part of the world?” cried hartley, indignantly.

“you ought to,” agreed frank, “and your assertion is proved, for there is the name!”

this was true.

upon the stern of the passing vessel was the name “aurelian.” that she was gilbert parker’s ship was a dead certainty.

that she had meant to run the submarine boat down was also a sure thing. it was an atrocious purpose, and made frank’s blood boil.

“the mean wretch!” he cried, angrily, “he certainly meant to run us down.”

“that he did!” cried hartley; “that is just like old parker.”

they discussed the matter, angrily. the aurelian was already half a mile away.

that she meant to recover the veneta’s treasure if possible before the dolphin was a certainty. the thought angered frank.

“i see the whole cowardly game!” he cried angrily. “and they shall pay for it well. they shall never carry home one penny of the veneta’s gold!”

“but what could we do against them?” asked hartley; “their ship is larger than ours.”

“you forget,” replied frank, “the torpedo boat is the most deadly craft in the u.s. navy. we can attack her on the same scale.”

“you are right,” cried the captain. “we surely need fear nothing from her. we could sail under her if we chose and sink her.”

“just so,” said frank. “at least i will give them a good lesson.”

he sprang into the pilot-house. he was about to give 25chase to the aurelian, when a warning cry came from barney, who had just come up from the engine-room.

“shure, sor,” he said, “there’s bad luck to pay!”

“what do you mean?” asked frank in surprise.

“the tank, sor, is out of order. shure, it must have been the shock av dynamite.”

“the tank!” exclaimed frank, and sprung to the key board. he pressed the pneumatic key. it would not operate.

the boat remained upon the surface. barney was right.

the tank was certainly out of order. but what was the cause of it? was it the result of the explosion?

he reckoned that this was true. he went down into the hold and made a quick examination.

this showed him that the tank had shifted its position, and bent the tubes so that water could not be pressed through them. until these were straightened there was no hope of controlling the boat under water.

frank studied the situation for some time.

he realized that it was an unfortunate situation, and that unless the matter was remedied the expedition must prove a failure.

just how much of a job it would be to repair the damage he could hardly estimate.

“well, frank,” cried clifford, “what do you think of it? is it an irreparable matter?”

“no,” replied the young inventor, slowly; “yet, to tell the truth, she ought to go into the dry dock. the tank should be moved back and properly stayed.”

“is it impossible to do that without going into the dry dock?”

“oh, yes.”

“then the game is up?”

“not yet,” said frank, hopefully, “there is a chance, i think we can readjust and straighten the tubes. if so, then we shall be all right.”

“but that will delay us!”

“certainly!”

“for how long?”

“a day!”

there was a dubious silence.

“then the aurelian will reach the gulf of honduras first. perhaps she may even recover the treasure.”

“let her, if she can,” said frank, “it will not be such an easy matter for her. she will have to send down divers and make many preparations which will take up time. we will get there about as soon as she does, i think.”

work was at once begun upon the twisted tubes.

barney and pomp brought all the necessary tools down into the place and operations commenced.

26as they progressed, frank found that the job was not to be as difficult as he had imagined.

the tubes were uncoupled and straightened, and the valves readjusted. but it required fourteen hours of hard work.

in the meanwhile the aurelian was long out of sight and well on her way into the gulf of honduras. she must surely reach the sunken galleon before the dolphin.

“fate seems to play a very important hand in this matter,” said clifford. “with all our accidents it is a wonder that we are able to reach honduras at all.”

“that is true,” agreed frank, “but let us hope that we shall meet with no more.”

“amen!”

the tank was now once more in working order. in other respects the dolphin was all right.

once again she set out for the continuance of her voyage.

darkness was now over the sea. yet the submarine boat, with her powerful searchlight was enabled to make fully as good time as in daylight.

it was in the afternoon of the next day that frank announced that they had passed through the yucatan channel and were really in the gulf of honduras.

once more the diagram as prepared from memory by clifford was consulted.

sailing by this for hours the dolphin kept on.

it was evening when they reached the locality where the donna veneta was supposed to have sunk.

“this is the spot as near as i can locate it,” said clifford.

“if that is true,” said frank, “we have outwitted parker, for the aurelian is certainly not in this vicinity.”

it was true that no vessel was in sight. the aurelian must have gone upon the wrong tack.

“what will we do?” asked captain hartley; “shall we wait until morning, or attempt to explore the ocean by electric light?”

“even in daylight we should have to use the searchlight,” said clifford eagerly. “suppose we examine it now, frank?”

“all right,” agreed the young inventor. “all is ready for the descent.”

the doors and windows were quickly and hermetically closed. then the dolphin plunged beneath the surface.

down she went for several hundred fathoms before the bottom was seen.

then a sandy plain lay before them.

“that is good!” cried frank. “it will be easier to find the donna veneta than if the bottom was covered with weeds.”

27“true,” agreed clifford. “i hope we will not be long in discovering her.”

all hands now posted themselves at the windows. the searchlight flashed everywhere across the sandy plain, while the boat moved slowly about in the quest.

all manner of curious objects were encountered. sometimes a huge projecting ledge of rock would be mistaken for the wreck.

and thus the search went on slowly and systematically. results were not far distant.