FiTzGrERALD & CuLLUM — Magnetic Observations at Valentin. 223 
The Meteorological Council having very kindly granted the necessary 
permission, a wooden observing-house, fastened with copper nails, and 
felted roof, was erected in the observatory grounds within 20 yards of 
the sea, lat. 51° 54' K, long. 10° 18' W. The house is provided with 
two concrete pillars, firmly embedded in the earth, on which the 
instruments are supported. 
A unifilar by Jones, and a dip circle by Barrow, with 3f in. needles, 
being available, were lent by Trinity College, together with a chrono- 
meter by Brockbank and Atkins, No. 879, hired for the purpose. The 
fittings of the collimator magnet having been altered to admit of it 
being used both for declination and force observations, it was sent to 
Kew to have its constants and corrections determined. It was there 
Sea Wall 
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Rain Gauges 
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Thermometer Screen 
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Magnetic 
House 
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Public Road 
iardened and re-magnetized, and on its return to Mr, CuUum he was 
iale to commence the series of observations in March last, the results 
which are appended. A reliable meridian mark being obtained on 
lie schoolhouse about two miles to the south-east of the observatory, 
8 orientation has been carefully determined by several series of Sun's 
Ititudes, and the instrumental readings are referred to it to determine 
[le magnetic variation. 
The observatory is situated on the south sound forming the Island 
Valentia, about 20 yds. from the shore, and 15 ft. above mean sea- 
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