"That was a queer thing to do," said one of the strangers to Dave, after the excitement was over. "Is he your enemy?" "He must be, but he is a stranger to me," answered our hero. The trip to San Francisco was made without anything special happening, and soon Dave and his father found themselves on board of the _Swallow_, which lay at her dock taking on the last of her stores for the long trip around the Pacific Ocean. After a number of inquiries, Amos Fearless learned that Lemuel Hankers had chartered the small steamer _Raven_, from the Wrecking Company, and had set sail on his treasure quest the day previous. "Never mind, we'll make up for lost time when once we get started," said Captain Broadbeam. "I fancy the _Swallow_ is a better boat in every way than the _Raven_." Two days later the _Swallow_ sailed with Mr. Fearless and Dave on board as master diver and assistant. The diving outfits on board pleased the master diver very much, and he was likewise greatly interested in the diving bell the ship carried. "That ought to be just the thing for our work," he said to Dave, "if they can let it down to where the wreck of the _Happy Hour_ rests." "But two miles is a tremendous distance, father." "I know it. I have never yet gone down over three hundred feet." "Perhaps we shall fail." "We must try a short distance first, Dave. We can't go down those two miles at the start. Captain Broadbeam wishes us to go down to-morrow anyway, to hunt for some strange fish, said to be in these waters, a fish known by the scientific name of Eurypharynx Pelecanoides." "What a fearful name!" muttered Dave. "Is the fish as bad?" "Yes, and worse. The monster is said to be all of twenty feet long, with a head larger than a hogshead and a mouth seven feet across. Its body and tail are covered with spines or stickers, and its teeth are like so many large needles." "Truly an ugly customer to meet," and Dave shuddered. "I am afraid he'll be an ugly customer to bag--in a net or otherwise." "Are we to use the diving bell?" "Yes, we are to try it, but we are likewise to use our diving suits, too--just to try both outfits," returned the master diver. The next day the _Swallow_ reached a section of the Pacific where the strange fish described by Amos Fearless was supposed to exist, upon the bottom of the ocean bed, half a mile below the surface. Diving suits were brought forth, and Mr. Fearless and Dave were not long in preparing to descend. Then the diving bell was adjusted to a long wire rope and let over the side, and they entered this. The word was given, and slowly but surely they descended into the cold and dark depths of the mighty Pacific. At a distance of two hundred feet the bright sunshine overhead began to fade away, and at five hundred feet it was as black as night, that is, some distance away from the diving bell. But around the bell several electric lights in the apparatus made all as bright as day.