Astounding Stories of Super-Science, August 1930

"Tens of thousands of green men they have prisoned here like us, for the sole purpose of supplying them with blood. For the Ralas live on this blood alone, changing it chemically to fit their own bodies and then taking it into their bodies. It eliminates all necessity for food here for them. Every few days they drain blood from us, and since we are well fed and cared for to keep us good blood-producers, we will be here for a long time before we die." "But haven't you made any attempt to get out of here--to escape?" Norman asked. Sarja smiled. "Who could escape the city of the Ralas? In all recorded history it has never been done, for even if by some miracle you got a flying-boat, the opening of the water-tunnel that leads outward is guarded always." "Guards or no guards, we're going to try it and not sit here to furnish blood for the Ralas," Norman declared. "Are you willing to help, to try to get to Fellows and your city?" The green man considered. "It is hopeless," he said, "but as well to die beneath the force-shells of the Ralas as live out a lifetime here. Yes, I will help, though I cannot see how you expect to escape even from this room." "I think we can manage that," Norman told him. "But first--not a word to these others. We can't hope to escape with them all, and there is no knowing what one might not betray us to the frog-men."