The Rell, a great and ancient Martian race, faced extinction when all moisture was swept from their planet. Then, one day, a lone visitor—a strange, two-legged creature composed mostly of water—landed on Mars … BY VERNON L. MC CAIN T he dehydration of the planet had taken centuries in all. The Rell had still been a great race when the process started. Construction of the canals was a prodigious feat but not a truly remarkable one. But what use are even canals when there is nothing to fill them?