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 life, upon Earth might easily have perceived all that Eveena discovered; but considering how seldom the latter had left her home, how few opportunities she had to see anything of practical agriculture, the quickness of her perception and the correctness of her inferences not a little surprised me. The path we pursued led directly to the object of our visit. The waters of the higher hills were collected in a vast tank excavated in an extensive plateau at the mid-level. At the summit of the first ascent we met and were escorted by one of the officials entrusted with the charge of these works, which supply water of extraordinary purity to a population of perhaps a quarter of a million, inhabiting a district of some 10,000 square miles in extent. The tank was about sixty feet in depth, and perhaps a mile in length, with half that breadth. Its sides and bottom-were lined with the usual concrete. Our guide informed me that in many cases tanks were covered with the crystal employed for doors and windows; but in the-pure air of these hills such a precaution was thought unnecessary, as it would have been exceedingly costly.

The water itself was of wonderful purity, so clear that the smallest object at the bottom was visible where the Sun, still high in the heavens, shone directly upon the surface. But this purity would by no means satisfy the standard of Martial sanitary science. In the first place, it is passed into a second division of the tank, where it is subjected to some violent electric action till every kind of organic germ it may contain is supposed to be completely destroyed. It is then passed through several covered channels and mechanically or chemically cleansed from every kind of inorganic impurity, and finally oxygenated or aerated with air which has undergone a