The Fernley Observatory, Southport : report and results of observations for the year 1898 / Borough of Southport Meteorological Department.

  • Southport (England). County Borough Council. Meteorological Department.
Date:
1899
Catalogue details

Licence: Public Domain Mark

Credit: The Fernley Observatory, Southport : report and results of observations for the year 1898 / Borough of Southport Meteorological Department. Source: Wellcome Collection.

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    The bulbs of the Solar Eadiation Maximum Thermometers are placed five feet above grass. To the readings of the Blackened-bulb Thermometer in vacuo a special subtractive correction is applied, for the purpose of rendering the indications of the instrument strictly comparable with those of the Kew Observatory’s standard Black-bulb Thermometer in vacuo. The photographic traces of the Jordan Sunshine Recorder are “ fixed” before being measured. The Direction of the Wind is given according to true, and not to magnetic bearings. When the air is practically calm at the time of observing, the point at which the Vane is standing is noted, and entered as the approximate direction. The cups of the Robinson Anemometer are five inches in diameter, and they are placed upon 12-in. arms. The Ozone Test-Papers and Scale used are Moffat’s, and are obtained from Messrs. Negretti & Zambra, London. The upper edge of the receiver of the Raingauge (a Meteorological-Office-pattern one, eight inches in diameter, and constructed of copper) is one foot above the surface of the ground, and 38 feet above mean sea level; this gauge is read twice daily, viz., at 9 a.m. and 9 p.m. A 5-inch Snowdon Raingauge, similarly placed, is employed for weekly and monthly check observations. The Duration of the Rain is registered by Casella’s Self-Recording Raingauge, as improved by Baxendell; the rim of this instrument is 4 feet 6 inches above the ground, and 42 feet above mean sea level. The Fog and other related Results are derived from observations of the visibility of objects and lights at definite distances from the Observatory Hill. The occurrence of Dew and Hoar-Frost is determined by the use of a thin compound board, painted wdiite, and supported by 2-inch pegs over a stout oak board let into the sod. Local Mean Time is employed for the Observations. The Averages, with which a number of the results for 1898 are compared in the following Tables, are (with the exception of the ones for Sunshine and Ozone) those for the 25 years 1872-96 inclusive. The adopted Jordan Sunshine Averages are those for the six years 1892-7 inclusive; and the adopted Ozone Averages, those for the eight years, 1891-8 inclusive. It seems scarcely necessary to add that the sign + in the columns headed “ Difference from the Average” signifies that the 1898 value exceeded the average by the amount following the sign, and that the sign — similarly indicates that the result for 1898 was below the average to the extent stated, p