the Residence. The hill selected stands about 4000 feet above the sea-level, and almost half that height above any neighbouring ground. It commands, therefore, a most perfect view of the horizon all around, even below the technical or theoretic horizon of its latitude. A volcano, like all Martial volcanoes very feeble, and never bursting into eruptions seriously dangerous to the dwellers in the neighbouring plains, existed at some miles' distance, and caused earthquakes, or perhaps I should more properly say disturbances of the surface, which threatened occasionally to perturb the observations. But the Martialists grudge no cost to render their scientific instruments, from the Observatory itself to the smallest lens or wheel it contains, as perfect as possible. Having decided that Eanelca was very superior to any other available site, they were not to be baffled or diverted by such a trifle as the opposition of Nature. Still less would they allow that the observers should be put out by a perceptible disturbance, or their observations falsified by one too slight to be realised by their senses. If Nature were impertinent enough to interfere with the arrangements of science, science must put down the mutiny of Nature. As seas had been bridged and continents cut through, so a volcano might and must be suppressed or extinguished. A tunnel thirty miles in length was cut from a great lake nearly a thousand feet higher than the base of the volcano; and through this for a quarter of a year, say some six Terrestrial months, water was steadily poured into the subterrene cavities wherein the eruptive forces were generated—the plutonic laboratory of the rebellious agency. Of course previous to the adoption of this