Dark Boundaries

When Commander Herries of the Space Line began to sell the water of Mars as a 'potion' for lengthening life he had no idea that he was going to create the world's greatest thirst and produce havoc among the two social grades of Earth - the Inelligentsia and the Normals. But produce it he did.

Among the confusion thus produced one man thinks clearly for his own ends - Vance Unthra, the leading scientist of the world - and he sees in the crisis which has hit Earth a way to be rid of all those ...