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Page:Popular Science Monthly Volume 80.djvu/134

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130
THE POPULAR SCIENCE MONTHLY

Hampshire hills averaged 3°–5° lower than at the Weather Bureau station in Boston, and that the nocturnal minima in the clearer air and at the higher altitude of my hillside were also several degrees lower than the disagreeably high minima of the city. The very regular occurrence of marked up-slope and down-slope ("mountain and valley") winds on all fine days; the increasing wind velocity towards noon and in the early afternoon, with calm mornings and evenings ("diurnal variation in wind velocity"), on these same days; the wonderful growth of cumulus clouds on the surrounding mountains and in relation to them; the development of cloud banners, cloud caps and cloud cascades; the effect of the general topography upon the local wind direction; the development of low-lying valley fogs at night, their gradual rise as fracto-stratus clouds and their dissipation under the morning sun; the marked difference, in relation to exposure to the cool nocturnal downhill breeze and to valley fogs, which neighboring house-sites exemplified; the apparent development of small local thunderstorms over the near-by mountains, while the larger thunderstorms came across these same mountains unaffected by the topography—these were a few of the many things which my very casual observations emphasized. Apart from these special subjects the general sequence of the larger weather changes resulting from cyclonic and anticyclonic controls was, of course, noted. So distinctly worth while has this simple and far from burdensome undertaking proved that I heartily recommend others to try it, but let it be repeated that real interest will come only if all previous meteorological knowledge of the region is, so far as possible, banished from the mind. And let me warn every one that he must beware lest his meteorological explanations run counter to the general traditions of the community. The location of most of the abandoned farmhouses in the region where I spent the summer, on the hillsides or even hill-tops, seemed to me to be most naturally explained on the theory that they were placed there in order that they might be above the cold and frost and fogs of the valley bottoms. One of my neighbors, who firmly believed that these houses were placed on the hill-slopes so that their original owners might have early warning of the approach of Indians, has upbraided me with shattering all the old and romantic traditions of the place. Let me suggest, further, that a very simple study of the value, as prognostics, of many weather proverbs will prove an interesting occupation. Weather proverbs are good, and bad, and indifferent. Most of them are bad, that is, do not work at all. A large number are indifferent, that is, work both ways. Comparatively few are really good. It is well worth while to select a few of the best known proverbs and keep careful written record of the times that each one "hits," and also of the times that each one "misses."