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308 familiar halo, can not be overlooked. It is the timely omen of impending disturbance, delivering its faithful warning long before the barometer begins to fall and tell its confirmatory tale. The accompanying cloud-illustrations, constructed, with some variations, after Mr. Ley's designs, will illustrate the chief weather-changes. Fig. 1 represents cirrus and cirro-stratus forming far in front of a cyclone, while yet the barometer has not begun to fall decidedly. Fig. 2 shows the cloud-system attending one of our storm-centers, as viewed from a point say 25,000 feet high (above the disturbance), the whole system borne along in the broad, horizontal "antitrade-wind" belt, from southwest to northeast, the scale of miles 200 to the inch, and the rate of progress fifteen miles an hour.

Could the rural populations and those whose occupation calls them much out of doors be assisted in interpreting these and similar phenomena, however untutored they might be in meteorologic terms and theories, they would soon learn to forecast many of the great weather-changes for themselves. But as the storm-signaling clouds, conspicuous to all, fly aloft in those mighty "upper currents" which, observation shows, attain not uncommonly velocities of one hundred and twenty and sometimes even one hundred and fifty miles an hour, none but strictly "simultaneous" weather-reports can adequately or truthfully reflect their actual, ever-flitting movements as related to storm-vortices and other atmospheric phenomena, whose approach and force they fore-token.

Once more. The most popular and profitable use to which meteorologic observations can possibly be put would be, if it is practicable, to forecasting in part the character of coming seasons—whether the next winter will be mild or severe, or the approaching summer wet or dry. It is certain that such forecasts will not be made until the network of observing stations is so enlarged as to record the temperature and other conditions over extensive portions of the oceanic, as well as the solid face of the globe. The northern hemisphere at least must be belted with stations returning simultaneous reports before season-predictions can be successfully attempted. But, with a broad girdle of observations around the middle latitudes, would it even then be possible to foreshadow the abnormal or extreme heat or cold of a coming summer or winter? It may seem premature to offer any reply to such an interrogatory; and yet it may not be as unanswerable as it seems. It is now pretty clearly ascertained that the earth in its orbital revolution is subjected to very decided periodic planetary influences, which sometimes destroy the balance of the seasons. The researches of Mr. Meldrum and others appear to corroborate the long-suspected physical connection between terrestrial cyclones and those grand solar atmospheric storms which produce or constitute sun-spots. A recent writer, summing up the latest results obtained from these and many like investigations, concludes that "the solar spots and temperatures