been his last dive.

He was aware of a large body moving near him and he dodged just in time
to avoid a collision, striking out for the surface. Lying flat on the
water, he peered into the depth and discovered several dark things
swimming about. Frightened at first, he remembered that sharks and
crocodiles do not live in mountain lakes. Bravely he descended, but
this time he swam with his bolo in his hand. Down, down, and again he
saw the queer, square things flopping about. They were huge tortoises,
clustered around a darker object at the very bottom of the lake. Once
more Piang came to the top. He was not afraid now; tortoises do not
fight unless attacked, and the boy could easily outswim any of the
clumsy creatures. But what were they doing out there in the middle of
the lake? Tortoises live near shoals and feed on fungi and roots. As
he plunged down once more, he was met by a strong up-current and had to
fight his way through. Tiny particles stung him as they rushed by, and
it seemed to him that millions of fish were darting here and there,
snapping at something. It was rice. Gradually it dawned on Piang
that he had reached his goal; the tortoise had reached it first,
and the secret lay hidden in that dark thing at the bottom.

Frantically, but steadily, he worked his way down, avoiding weeds and
driftwood. The water grew calmer as he neared the bottom, the rush of
the current less. His breath was almost gone; he could hardly stand
it a few seconds longer, but he must see what it was there. With one
supreme effort, he struggled and reached the hard sand of the lake
floor. A trifle dazed, he looked about, and there, towering above him,
was a ship.

Piang was almost unconscious when he reached the air. Had he
been dreaming? How could a ship be resting on the bottom of Lake
Lanao? Restraining his curiosity, he forced himself to rest. Lying on
his back again, he took long regular breaths until he was entirely
rested. Slowly he descended and, avoiding contact with the loggy
tortoise, circled around the dark thing. Yes, it was a boat. Piang
had seen only one other boat like it in his life. It was only about
thirty-five feet long, but to the boy it seemed to rise above him
like a mountain. Fascinated, he sank lower until he was standing on
the deck. The tortoises and fish paid no attention to him, and he
examined it carefully. The big tube, sticking up in its middle Piang
recognized as the thing that belches smoke, and