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 for these trials, by transferring her demonstrations lower down. The Observatory then enjoys clear sunshine for days and weeks, whilst all below is enveloped in impenetrable mist and fog.

Nothing of this sort, bitter though the weather may be in all parts of the British Isles, is ever seen at the Kew Observatory, to which we are about to pay our hasty visit, under the kindly guidance of Mr. G. M. Whipple, the superintendent. As you approach the Observatory, the first thing you notice and want to know all about, is the anemometer on the top. Four cups at the end of short iron rods are whirling more or less rapidly, according as there is much or little wind. These, you learn, are in connection with an instrument inside the building, which records the rate at which they turn, and consequently the rate at which the wind is travelling. Sometimes Master Boreas takes it in his head to fly over the earth's surface at the not very moderate rate of ninety miles an hour; at others he is content with a few miles in that time. Whatever he does, his pace is infallibly noted. A cylinder revolves by clockwork. When there is little wind, a pencil which touches the paper on the cylinder travels along it horizontally, but when there is much wind it travels across it more or less perpendicularly, as it were. Thus the inclination at which the pencil line runs round or along the paper indicates the rate at which the wind has passed over the earth's surface. Sometimes it will go for a day right along the cylinder—that will show calm; sometimes it will go a little way along, then suddenly begin to move across it, or at any rate to incline downwards: that would indicate that from a calm there had suddenly sprung up a considerable breeze. Self-recorders are con-nected also with (1) the barometer, the rise and fall of the mercury being continuously photographed, (2) the magnetometer which, placed in a cellar, marks any magnetic disturbance underground, the movements of the needles being photographically recorded by an ingenious arrangement of