"But what did the Pict mean by the Nuptials of the Moon?"

Wulfhere looked at Cormac and Cormac started to speak, shot a quick glance at Marcus and hesitated.

"Tell him," nodded Donal. "He must know eventually."

"The Picts worship strange and abhorrent gods," said the Gael, "as is well known to we who roam the sea, eh Wulfhere?"

"Right," growled the giant. "Many a Viking has died. on their altar stones."

"One of their gods is Golka of the Moon. Every so often they present a captured virgin of high rank to him. On a strange, lonely isle in the Shetlands stands a grim black altar, surrounded by columns of stone, such as you have seen at Stonehenge. On that altar, when the moon is full, the girl is sacrificed to Golka."

Marcus shuddered; his nails bit into his palms.

"Gods of Rome, can such things be?"

"Rome has fallen," grunted the Skull-splitter. "Her gods are dead. They will not aid us. But fear not-" he lifted his gleaming, keen-edged axe, "here is that which will aid us. Let me lead my wolves into the stone circle and we will give Golka such a blood-sacrifice as he has never dreamed of!"

"Sail on the port bow!" came the sudden shout of the look-out in the cross-trees. Wulfhere wheeled suddenly, beard bristling. A few moments later all on board could make out the long, low lines of the strange craft.

"A dragon-ship," swore Cormac, "and making full speed with oar and sail-she means to cut across our bows, Wulfhere."

The chieftain swore, his cold blue eyes beginning to blaze. His whole body quivered with eagerness and a new roaring note came into the voice that bellowed commands to his crew.

"By the bones of Thor, he must be a fool! But we'll give him his fill!"

Marcus caught the Dane's mighty arm and swung him about.

"Our mission is not to fight every sea-thief we meet," the young Briton cried angrily. "You were engaged to search for the princess Helen; we must not jeopardize this expedition. Now we have at last a clue; will you throw away our chances merely to glut your foolish lust for battle?"