PROCEEDINGS
OF
THE ROYAL SOCIETY.
May 21, 1840.
The MARQUIS of NORTHAMPTON, President, in the Chair.
William Burge, Esq., Walter Ewer, Esq., Thomas Tassell Grant, Esq., and Henry Lawson, Esq., were balloted for, and duly elected into the Society.
The following papers were read, viz. :
1. " Remarks on the Meteorological Observations made at Alten, Finmarken, by Mr. S. H. Thomas in the years 1837, 1838, and 1839." By Major Sabine, R.A., V.P.R.S., and Lieut .Col. Sykes, F.R.S. ; being a Report from the Committee of Physics, including Meteorology, to the Council, and communicated by the Council to the Royal Society.
These observations, made at Alten in lat. 69° 58' 3" N., and 23° 43' 10" east of Paris, would seem to have a claim to the attention of the Royal Society, as they offer the experimentum crucis of Professor Forbes's empirical formula respecting the gradual diminution of the daily oscillations of the barometer, within certain limit hours, from the equator to the poles. Professor Forbes has laid down an assumed curve, in which the diurnal oscillation amounts to '1190 at the equator and in lat. 64° 8' N., and beyond that latitude the tide should occui with a contrary sign, plus becoming minus. Now Alten being nearly in lat. 70°, if Professor Forbes's law hold good, the maxima of the diurnal oscillations should occur at the hour for the minima at the equator, and a similar inversion should take place with respect to the minima. Mr. Thomas has himself however modified the value his observations would otherwise have had, by adopting 2 p.m., instead of 3 p.m., for the hour of his observations for the fall; and he has adapted his barometrical observations to a mean temperature of 50° Fahr., instead of 32°. The first year's observations commence on the 1st October, 1837, and terminate on the 30th September, 1838. The barometer stood 66 feet 5 inches above low- water mark, and the thermometer hung at 6 feet above the ground ; but care was not always taken to prevent the sun shining on it. The mean height of the barometer for the year was 29°'771, and the mean of the thermometer almost coincident with the freezing point, viz., 32°'017. The
