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vestigations may be carried on which could not be brought to successful conclusion at the central office in St. Petersburg. This new physical observatory consists of a principal stone building, with a high tower for anemometric observations, and contains physical, chemical, and photometric observatories, workshops, etc. A magnetic apparatus of the most complete nature is established in a subterranean cellar room. Dwellings for the officials will also be erected. The entire cost will not be far from one hundred thousand dollars in gold. The erection of the new building will begin in the spring of 1876. The annual appropriation for the institution will amount to thirteen thousand dollars, while the similar appropriation for the central institution at St. Petersburg, which amounts to thirty-six thousand dollars, will not be dininished, in order that it may carry on to completion the great works already begun.-Vienna Zeitschrift für Meteorologie, X., 293.

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THE HURRICANE OF SEPTEMBER 9TH TO 1779, 1875. The hurricane of September 9th to 17th is described in the Monthly Weather Review of the Army Signal-office as one of the most violent that has occurred since the establishment of the Weather Bureau. It was first observed in latitude 13° north, longitude 17° east from Washington, and appears to have originated to the east of Barbadoes. Passing thence toward the west-northwest, its path curved around, striking the coast of Texas, whence it moved toward the northeast until it disappeared in latitude 38° north, longitude 6° east. On the 14th the morning reports announced that the centre of the storm had already passed to the westward of Key West and Havana. Very perfect records of the changes in the barometer and winds have been preserved at the Galveston and Indianola stations, at which place it was at its height on the 16th and 17th. The lowest barometers were, at Galveston 29.04, and Indianola 28.90. The maximum velocity of the wind at Galveston was sixty miles per hour, from the southwest and west. The maximum at Indianola was eightyeight miles per hour, from the northeast, as registered by the anemometer. This instrument having however been destroyed by the continued gale, it was estimated that the velocity subsequently attained one hundred miles per hour.

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The extreme severity of the storm seems to have been felt on the coast of Texas. In its subsequent course it extended over a larger area, and seems to have produced heavy gales on the Jersey coast, and to have had some connection with the violent storms which prevailed on the North Atlantic Ocean to the north of Great Britain from the 26th to the 29th of September. The heavy rains that accompanied the storm during its prevalence over the Gulf of Mexico contributed to the large excess of precipitation which prevailed in the Gulf States for the month of September. --- Monthly Weather Review for September, 1875.

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THE DIRECTION OF CIRRUS CLOUDS. The movement of the cirrus clouds has been the subject of study by Hildebrandsson, of Upsala, who bopes thereby to deduce some results relative to the ascending and descending movements of the atmosphere above the regions of high and low barometer. The observations of Clement Ley show that the cirrus clouds move from areas of minimum toward areas of maximum pressure, and Hildebrandsson has endeavored to extend this interesting generalization over a wider field. He states, in fact, that a general study of the clouds over the whole of Europe shows him that while the air on the earth's surface moves in spiral curves, inward, toward low barometer, the air at a high altitude simultaneously moves outward. The upper winds, therefore, constantly make an angle toward the right with the lower winds. This demonstration was in 1871 also made by Abbe for the United States, and may probably now be considered as a general rule, applicable throughout the world. It is important to notice that the same conclusion was arrived at deductively by Ferrel in 1857, and is fairly stated in his great work on the motions of bodies on the earth's surface.

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THE TEMPERATURE OF THE EARTH. The interest which attaches to careful observations of the temperature of the earth suggests that the apparatus which is used in Germany should be better known in this country, in order that, when practicable, it may be introduced here. The following is a description of it as used by observers in Hungary. In its general outlines it does not differ from that

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GENERAL LIBRA

University MIORIGA

B. TERRESTRIAL PHYSICS AND METEOROLOGY.

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recommended by Lamont. It consists principally of a rect-
angular tube buried permanently in the earth, within which
five rectangular prisms of wood are placed, one above the
other, at different depths in the ground, and which, by a sim-
ple arrangement, can be easily and quickly drawn up. Each
of these tubes contains a thermometer, and there is a hole in
the side of the main tube, opposite to the bulb of the ther-
mometer, where the wood-work is cut away, and the opening
closed by a plate of thin sheet copper, whose temperature
may be presumed to be the same as that of the adjacent
ground. The depths at which the thermometers' bulbs re-
main are 4, 8, 12, 16, and 20 feet. Schenzl, as the result of
observations made during eight years, finds that the time
required for heat to penetrate to a depth of one meter is, on
the average, 21 days.

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THE INTENSITY OF TWILIGHT.
Mr. Williams, a student of the Massachusetts Institute of
Technology, has made some observations to determine the
quantity of light reflected during the hours of twilight, when
the sun is at different distances below the horizon. The pho-
tometer employed was a slight modification of the Bunsen
photometer. The illuminated disk was exposed on one side
to the light from a standard candle, and on the other side to
the light admitted from the sky.- Proceedings Am. Acad.
Arts and Sciences, 1875, 421.

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ON THE QUANTITY OF LIGHT REFLECTED BY THE SKY IN THE

DAYTIME.
The quantity of light reflected by the sky at any given
distance from the sun has long been a subject of meteoro-
logical observation, the first rude attempt at its measurement
being made by the use of Saussure's cyanometer. Some elab-
orate investigations have been pursued for a long time at
the Mont-souris Observatory. An interesting investigation
of the question by a simple photometric apparatus has re-
cently been published by Crosby as a student under Profess-
or Pickering of the Institute of Technology at Boston. His
objects were to determine, first, the absolute amount of light
received from the sky at different distances from the sun, and
second, to ascertain the law of diminution of light with in-

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The extreme severity of the storm seems to have been felt on the coast of Texas. In its subsequent course it extended over a larger area, and seems to have produced heavy gales on the Jersey coast, and to have had some connection with the violent storms which prevailed on the North Atlantic Ocean to the north of Great Britain from the 26th to the 29th of September. The heavy rains that accompanied the storm during its prevalence over the Gulf of Mexico contributed to the large excess of precipitation which prevailed in the Gulf States for the month of September.- Monthly Weather Review for September, 1875.

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THE DIRECTION OF CIRRUS CLOUDS. The movement of the cirrus clouds has been the subject of study by Hildebrandsson, of Upsala, who hopes thereby to deduce some results relative to the ascending and descending movements of the atmosphere above the regions of high and low barometer. The observations of Clement Ley show that the cirrus clouds move from areas of minimum toward areas of maximum pressure, and Hildebrandsson has endeavored to extend this interesting generalization over a wider field. He states, in fact, that a general study of the clouds over the whole of Europe shows him that while the air on the earth's surface moves in spiral curves, inward, toward low barometer, the air at a high altitude simultaneously moves outward. The upper winds, therefore, constantly make an angle toward the right with the lower winds. This demonstration was in 1871 also made by Abbe for the United States, and may probably now be considered as a general rule, applicable throughont the world. It is important to notice that the same conclusion was arrived at deductively by Ferrel in 1857, and is fairly stated in his great work on the motions of bodies on the earth's surface.

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THE TEMPERATURE OF THE EARTH, The interest which attaches to careful observations of the temperature of the earth suggests that the apparatus which is used in Germany should be better known in this country, in order that, when practicable, it may be introduced here. The following is a description of it as used by observers in Hungary. In its general outlines it does not differ from that

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University WIARIGA

B. TERRESTRIAL PHYSICS AND METEOROLOGY.

recommended by Lamont. It consists principally of a rect-
angular tube buried permanently in the earth, within which
five rectangular prisms of wood are placed, one above the
other, at different depths in the ground, and which, by a sim-
ple arrangement, can be easily and quickly drawn up. Each
of these tubes contains a thermometer, and there is a hole in
the side of the main tube, opposite to the bulb of the ther-
mometer, where the wood-work is cut away, and the opening
closed by a plate of thin sheet copper, whose temperature
may be presumed to be the same as that of the adjacent
ground. The depths at which the thermometers' bulbs re-
main are 4, 8, 12, 16, and 20 feet. Schenzl, as the result of
observations made during eight years, finds that the time
required for heat to penetrate to a depth of one meter is, on
the average, 21 days.

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THE INTENSITY OF TWILIGHT.
Mr. Williams, a student of the Massachusetts Institute of
Technology, has made some observations to determine the
quantity of light reflected during the hours of twilight, when
the sun is at different distances below the horizon. The pho-
tometer employed was a slight modification of the Bunsen
photometer. The illuminated disk was exposed on one side
to the light from a standard candle, and on the other side to
the light admitted from the sky.- Proceedings Am. Acad.
Arts and Sciences, 1875, 421.

ON THE QUANTITY OF LIGHT REFLECTED BY THE SKY IN THE

DAYTIME.
The quantity of light reflected by the sky at any given
distance from the sun has long been a subject of meteoro-
logical observation, the first rude attempt at its measurement
being made by the use of Saussure's cyanometer. Some elab-
orate investigations have been pursued for a long time at
the Mont-souris Observatory. An interesting investigation
of the question by a simple photometric apparatus has re-
cently been published by Crosby as a student under Profess-
or Pickering of the Institute of Technology at Boston. His
objects were to determine, first, the absolute amount of light
received from the sky at different distances from the
second, to ascertain the law of diminution of light with in-

sun, and

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