They stepped out of the end of the passage and found themselves in the open sea, many fathoms down. A broad and slightly sloping floor of smooth sand studded with lumps of coral and clusters of sea-weed stretched before them. Some were giant ferns stretching twelve and fifteen feet high, others were low and sponge-like growths. A school of tiny red fishes shot swiftly past them. Larger fish sailed majestically by overhead. The top of the water was a gleaming golden ceiling far above them, the greenish yellow light lessening in intensity as it came down to the depths. The end of the passage was surrounded by a barrier of piled coral. Outlaw swordsmen stood on guard, also armed with a sort of compressed air cross-bow that shot a heavy metal needle with great force. From a corral at one side an orderly brought three saddle-dolphins. The big fish were equipped with rubber saddles strapped around the body, and short stirrups. They were guided by a bridle similar to that used on Earthly horses. As Gerry swung up to the saddle his dolphin bucked once or twice with quick flips of his tail, then steadied down as he felt the tight pressure of his master's knees. When the other two were mounted, the officer commanding the outpost lifted his arm in salute. "The Dragon Gods be with you!" he said. At a distance of fifteen or twenty feet the sound of his voice was slightly muted, but the words were perfectly clear in the ear-pieces of Gerry's helmet. He lifted his own rubber gloved hand to his globular helmet and returned the salute. * * * * * They rode off at an easy pace, the dolphins rising above the tops of the tallest vegetation. Gerry found that it was easy to sit the saddle as long as he bent a little forward to overcome the resistance of the water against his chest. They were about thirty or forty feet down. On Earth such a depth would have been uncomfortable, but the lighter gravity of Venus made it easily bearable. Gerry glanced back. Closana was riding a few feet behind him, slender and erect, controlling her restless dolphin as easily as though she had been accustomed to such steeds all her life. Angus was grinning broadly through his globular glass helmet as he sat astride a particularly big dolphin and swung his light bladed water-sword from side to side. "If any of our friends back on Earth could see us now in some sort of an astral spectroscope," the big Scot cried, "they'd think themselves crazy. Maybe this is only a nightmare at that! Do you think we'll wake up soon and find ourselves safe back on board the _Viking_?" "I'm afraid not," Gerry answered. He wondered in what part of this vast sea the twisted hulk of the _Viking_ was now lying.