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Show ANNOTATIONS AND ADDITIONS. 117 of the country to possess a proper continental character, i.e. hotter summers and colder winters. "It is proved," says Forry, "by our thermometrical data, that the climate west of the Alleghany Chain is more excessive than that of the Atlantic side." At Fort Gibson, on the Arkansas River, which falls into the 1\fississippi in lat. 35° 47', with a mean annual temperature hardly equal to that of Gibraltar, the thermometer in the shade, and without any reflected heat from the ground, has been seen, in August 1834, to rise to 37°.7 Reaumur, or 117° Fahrenheit. The statement so often repeated, although unsupported by any thermometric measurements, that, since the first European settlements in New England, Pennsylvania and Virginia, the eradication of many forests on both sides of the Alleghanies had rendered the climate more equable (i. e. milder in winter and cooler in summer), is now generally doubted or disbelieved. Series of trustworthy thermometric observations in the United States hardly extend so far back as seventy-eight years. We sec in the Philadelphia observations, that, from 1771 to 1824, the mean annual temperature has hardly increased 1°.2 Reaumur (or 2°.8 Fahrenheit)-a difference which is attributed to the increased size of the town, to its greater population, and to the numerous steam-engines. The difference may possibly be merely accidental, for I find in the same period an increase of mean winter cold, amounting to 0°.9 Reaumur, or 2° Fahrenheit; the three other seasons had become somewhat warmer. Three-and-thirty years' observations at Salem, in Massachusetts, show no alteration at all: the annual means oscillate, within a degree of Fahrenheit, about the mean of the whole number of years; and the winters of Salem, instead of having become milder, as supposed from the destruction of the forests in the course of the thirtythree years, have become colder by 1°.8 Reaumur, or 4° Fahrenheit. (Forry, pp. 97, 101, and 107.) As the east coast of the United Sta.tes is comparable in respect to mean annual temperature, in equal latitudes, to the Siberian and Chinese coasts of the Old Continent, so also the west coasts of Europe and America have been very properly compared together. I will only take a few examples from the western region on the shores of the Pacific, for two of which (Sitka in Russian America, and Fort |