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them from frost, we should in this case also cover the soil with grass.—19.C, XIV., 135.

AQUEOUS VAPOR IN THE ATMOSPHERE. The Academy sums up the conclusions of Dr. Hildebrandson, of Upsala, in regard to aqueous vapor in the atmosphere, as follows: 1. The permanent gases in the atmosphere do not form independent atmospheres, but have effected a complete mutual interpenetration; as all experiments show that the constitution of the air is the same at all heights. 2. The incessant evaporation and condensation which are in progress render impossible the existence of an independent vapor atmosphere, or of a homogeneous mixture of the vapor with the permanent gases, and must cause the vapor to diminish rapidly with height. 3. It is not allowable to subtract the vapor pressure from the barometer reading to obtain the pressure of dry air. -13 A, Feb. 6,1875, 145.

THE NEW ANEMOSCOPE. Michelle describes an ingenious anemoscope in which three arrows are used, of which the upper one indicates the direction of the wind at each moment. The second indicates the extreme wind on the right, and the third indicates the extreme wind on the left hand. Thus, when one looks at the wind vane, we see not only the wind that now prevails, but the extreme winds on either side that have prevailed since the preceding observation. Bulletin Hebdomadaire, XVI., 12.

PERIODICITY OF RAINFALL.

Governor Rawson, of the island of Barbadoes, whose remarkable studies upon the rainfall of that island have been already noticed, states that it is an error to suppose, as Mr. Meldrum does, that the observed rainfall in Barbadoes in any way really supports Mr. Meldrum's theory that there is a sun-spot period in these meteorological phenomena. IIc, however, very philosophically adds that, if the conclusions drawn from a wide area and very long periods of observation do support that theory, then the opposite results obtained in Barbadoes, although that island is most favorably situated for these observations, only show that no particular locality can draw a safe inference as to the manner in which the presence or absence of sun spots is likely to affect it.

But looking more deeply into the matter, Governor Rawson very justly adds that if there has been more rain in certain quarters of the globe in certain years, there must have been in other quarters during those same years greater evaporation, whence it results that the same solar phenomena produce in one portion of the world opposite effects to those produced elsewhere.-12 A, X., 264.

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MARITIME CONFERENCE IN LONDON. At the recent Maritime Conference in London the resolutions adopted by the meeting embraced the following subjects. It was resolved that there should be but one form of meteorological register for naval and merchant services, and that so far as possible a uniformity in methods and hours should be observed. Ocean currents and magnetic variations were recommended for observation. The upper and lower clouds are to be recorded in separate columns. The precise patterns of instruments were not specified, the only reqnirement being that those used should satisfy certain tests, and that they should be carefully compared with standard instruments. It is considered that the general influence of the Conference was decidedly in favor of united action on the part of the merchant service and the navies of the world. Particular stress was not laid upon the conducting of special investigations by sea-captains, as such can be most economically performed at the central meteorological stations and by government naval vessels.--12 A, X., 431.

THE TEMPERATURE OF STORMY WINDS, Dr. Fritsch, of Vienna, communicates to the Annual of the Vienna Meteorological Institute some observations on the temperature of the storm-winds at Salzburg. He states that, since 1864, he has every summer resided in Salzburg without noticing the high temperatures of the southeast storm-winds; but that since he has resided there constantly during the past few years, this has been forcibly brought to his attention, as also the great dryness which accompanies these winds. From the records made at 7 A.M., and 2 and 9 P.M., from 1863 to 1869, he has selected the stormy winds, and

finds that both the southeast and northwest storms experienced at that place are much modified by the influence of the Alps. The southeast, or föhn, wind has, at all seasons and at all points, a notably high temperature, the exception only being in the three summer months, in which the föhn decidedly depresses the temperature. In the winter and summer the temperatures of the southeast and northwest storms are nearly the same, but in the spring and fall the southeast are decidedly warmer than the northwest storms. In the high southeast winds the air is clear and dry, but in the northwest cloudy and moist.

ON ATMOSPHERIC PRESSURE, WINDS AND RAIN. A recent supplementary volume of Dr. Petermann's geographical notes gives us a comprehensive memoir on our present knowledge of the atmospheric circulation by Dr. A. Wojeikof, which is accompanied with highly interesting and valuable charts; the last of the charts gives us a new view of the distribution of rain over the earth, in that it distinguishes between the areas of summer and winter rains, besides giving us the results of the most recent investigations as to the general distribution of the rain-belts of the earth. In general, Dr. Wojeikof finds that between the poles and 40° of latitude the rainfall is liable to occur at all seasons of the year, the variations being seasonal in their nature. Thus Siberia and British America receive most of their rains in the summer time; Great Britain, Norway, France, and Portugal receive their rains in the fall. Between these polar regions and the rainless zone of the trade-winds Wojcikof introduces belts of sub-tropical rains, which are, he thinks, essentially oceanic, while the polar rain-belts are essentially continental. In considering the distribution of rain in Siberia, he states a law which, verified by independent observations, is a remarkable confirmation of a theoretical deduction due to Mr. Ferrell. According to Dr. Wojeikof, the atmospheric pressure in winter in the higher latitudes is lower over those seas that have no connected ice-fields. According to Mr. Ferrell, the pressure in the polar regions of the earth is lower in proportion as we diminish the frictional and other resistances offered by the earth to the movement of the air. If, therefore, the resistance offered by fields of ice is sensibly greater than those offered by the open sea, or small ice-floes, then Professor Ferrell's proposition explains at once Dr. Wojeikof's generalization.-Petermann's Mittheil., Ergänzungsh., No.38.

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THE IMPORTANCE OF METEOROLOGY. The annual report of the Radcliffe Observatory, delivered at Oxford, June 29, states that the principal labors at that institution continue, as formerly, to be given to the transit circle and the heliometer, and that the meteorological observations made at that observatory are reduced much more elaborately than is done at the greater number of astronomical observatories, and are presented to the public in the most scientific shape that they admit of. “I am also of the opinion that they are worthy of the labor which is bestowed upon them, and I differ in opinion from some eminent authors as to the rank which meteorology already occupies among the physical sciences. At all events, I think a similar system of reduction should be employed at other observatories.”

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SECULAR CHANGES OF CLIMATE. “The Indications of Spring" is the title of a work communicated to the Royal Society, in 1789, by Mr. Robert Marsham. These indications were based upon observations, commencing in the year 1736, by Robert Marsham, and which were continued until 1812 by his descendants of the same name. The record was again begun in 1836, and continued until the present time by the Rev. H. P. Marsham. This record of one hundred and forty years which we owe to the Marsham family has preserved innumerable notes in reference to botanical and other natural-history phenomena, and, for a greater portion of the time, the record was very full and careful, the first Mr. Marsham being an observant naturalist, and exceedingly fond of rural pursuits. An analysis of these observations has recently been presented by Thomas Southwell to the Naturalist Society of Norfolk and Norwich, who states that, as it has often been stated that “our old-fashioned winters have departed," and that the springs have become later, he has sought to test the question by taking the average days of the occurrence of twenty-five different phenomena indicative of the seasons during the years 1763 to 1774 inclusive. He did the same with the ten years ending

1874, and finds that the average date corresponding to the whole twenty-five phenomena is, for the eighteenth century, April 7, and for the nineteenth century March 28, showing that the springs are now nine days earlier than they were one hundred years ago. These dates are based respectively upon 196 and 181 observations; and it is not probable that the difference is owing to any fault of observing, but it is possibly due to drainage or cultivation. The extreme variability even of the English climate is illustrated by the range in the dates of certain phenomena. Thus, turnips are reported in flower December 25, 1846, and May 14, 1784. The wood-anemone was observed in flower March 9, 1775, and April 30, 1837. The average range of phenomena noted by Mr. Marsham is about seventy days. -- Transactions of the Norfolk and Norwich Naturalist Society, 1875, 46.

METEOROLOGY IN NEW SOUTH WALES. The private observatory of Mr. John Tebbutt, of Windsor, New South Wales, contributes to the meteorology of that part of the world a volume of observations made from 1867 to 1870, which observations have been recorded regularly at 9 A.M., and are supplemented by the records of self-registering maximum and minimum thermometers. The geographical position of the observatory has been determined by an extended series of observations of moon-culminating stars for longitude, and by observations in the prime vertical for latitude. The observatory is also connected by telegraplı with the Sydney Observatory, which has, until recently, been under the directorship of Rev. W. Scott. The observatory of Mr, Tebbutt is situated on a hill near the centre of the peninsula at the eastern extremity of the town of Windsor. It is about 28 miles from the sea-coast on the east, and about 8 miles from the Blue Mountains on the west, and is surrounded by the forest except in its immediate neighborhood, where the soil has been cleared and cultivated for more than fifty years. Many of the meteorological instruments used in these observations were made in Sydney; others were brought from England, where they had been carefully compared with accepted standards. From the tables given in this volume of observations, it appears that the total amount of rain, as mcasured at Windsor, has been, in 1867, 44 inches;

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