"Look out!" cried Tom. But he was too late. Koku raised his axe and struck with all his force at the sea beast. He hit it a glancing blow, not enough to kill it, but to wound it, and immediately the sea was crimsoned with blood.
The devil fish was able to observe under water better than its human enemies, and it was in no doubt as to its assailant. In an instant it attacked the giant, seeking to pierce him with the deadly tail.
These tails are not only armed with a tip of horn-like hardness, they are also poisonous, and their penetrating power is great. Fishermen have sometimes caught small sting rays, which are a sort of devil fish. Lashing about in the bottom of a boat a sting ray can send its tail tip through the sole of a heavy boot and inflict a painful wound which may cause serious results.
The beast Koku had wounded was trying to sting the giant, and the latter, aware of his peril, was striking out with the axe.
"Look out, Tom!" called Ned through his telephone, as he saw one of the two unwounded devil fish swirl down toward the young inventor. Tom looked up, saw the big, horrible shape above him, and jabbed it with the sharp, steel bar. He inflicted a wound which added further to the crimson tinge in the sea, and that fish now attacked Tom Swift.
In another instant all three divers were fighting the terrible creatures, that, knowing by instinct they were in danger, were using the weapon with which nature had provided them. They lashed about with their sharp-pointed tails, and more than one blow fell on the suits of the divers.
Had there been the least penetration, of course almost instant death would have followed. For the sea, at that depth and pressure, entering the suits would have ended life suddenly. But Tom had seen to it that the suits were well made and strong, with a lining of steel. And however great a thickness of leather the devil fish could send his sting through, it could not overcome steel.
There was danger, though, that the slender tip might slip through the steel bars across the windows in the helmets and shatter the glass. And that would be as great a danger as if the suits themselves were penetrated.
"We've got to fight 'em!" gasped Tom through his instrument, and, seeing his chance, he gave another jab to the devil fish attacking him. Koku, too, was standing up well under the attack of the monster he had first wounded. Ned, watching his chance, got in several blows, first at one and then at the other of the huge creatures. The third devil fish, which had not been wounded, had disappeared. Finally Koku, with a desperate blow, succeeded in severing the tail from the beast attacking him, and that battle was over.
As if realizing that it had lost its power to harm, the devil fish at once swam off, grievously wounded. Then Koku turned his attention to Tom's enemy. Ned, too, lent his aid, and they succeeded in wounding the creature in several places, so that it sank to the bottom of the sea and lay there gasping.