The Sirens of Titan

Unk found a big blue stone outside the furnace room of barrack twelve. The stone was a turquoise. Turquoises are very common on Mars. The turquoise Unk found was a flagstone a foot across. Unk looked under it. He found an aluminum cylinder with a screw cap. Inside the cylinder was a very long letter written in pencil. Unk did not know who had ... ................
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