It looked like ground-up lava. Gray-black, almost a powder, it had a faintly sulphurous smell. As he turned it speculatively in his hand, wondering how he was supposed to use it, a few grains sifted between Chris's fingers and fell over the side into the sea. Instantly, as soon as they touched the water, several infinitesimal flames started up, burning on the waves as hardily as if they had fallen onto dry grass, and their heat produced a sturdy mist which rose in heavy spirals from every grain. Then Chris knew what it was for. Shaking every particle carefully back into the bag, he hurried to find Captain Blizzard. "Sir!" he cried as soon as he was within earshot, "the pirates are bested, and we can make a safe escape if you will give an order to set loose the grappling irons and lines and bid our men raise sail!" He looked eagerly at Captain Blizzard. "The pirates look pretty tired now, but the _Vulture_ might pursue us if I didn't know a way to stop her!" The Captain looked thoughtfully at Chris and hesitated not at all. Too much had already depended on the boy and had been faithfully carried out for even Captain Blizzard to doubt of his ability. Orders were quickly given to cast off from the pirate ship and Chris disappeared to a hidden corner. There he hid everything the leather bag had contained excepting the grainy powder. Next, taking the bag from around his neck and leaving the mouth of it wide open, he changed his shape to that of a sea gull. Taking the pouch in its beak the gull soared high above the two vessels, now drifting imperceptibly apart. Sounds of violent fighting could still be heard inside Claggett Chew's cabin, but the pirate crew seemed grateful enough to fall to the bloody decks to rest and care for their wounds. As the two ships finally stood clear of one another, a resounding cheer of victory rose from the courageous members of the _Mirabelle_. Their shirts ripped into hasty bandages, their bodies glistening with sweat and rusty with their own or their foes' blood, they were a bedraggled sight. Nevertheless, as they raised their arms or flung their caps into the air, flinging after the pirates a few last resounding epithets. Chris's heart swelled with emotion at the men he was proud to call his friends. As the gull, he swung up into the air away from the _Mirabelle_, and began shaking the dust from the open pouch on the sea around the _Vulture_. By the time the bag was empty, a mist impossible for any helmsman to see through had surrounded the battered ship from stem to stern, and in despite of a freshening wind, was rising steadily to the top of its one remaining mast.