376 Proceedings of the Royal Society of Edinburgh. 
Ordinary Members. 
James Hunter, Esq. of Thurston. 
Right Honourable David Boyle. 
James Keith, Esq. 
Right Honourable Sir Samuel Shepherd. 
James Nairne, Esq. 
John Colquhoun, Esq. 
Henry Raeburn, Esq. 
Lieutenant-Colonel M. Stewart. 
Charles Babbage, Esq. F. R. S. 
Thomas Guthrie Wright, Esq. 
John F. Herschel, Esq. F. R. S. 
Adam Anderson, Esq. A. M. 
John Shank More, Esq. 
William Hall, Esq. A. M. 
Dr George Augustus Borthwick. 
Robert Dundas, Esq. of Arniston. 
Dr Samuel Hibbert. 
.James Robinson Scott, Esq. 
Dr Robert Haldane. 
Feh. 7. — A paper by the Rev. Mr Holland was read, On the 
Radiation of Caloric, and the apparent Radiation of Cold. 
At the same meeting, a paper by Dr Brewster was read. On 
the Mean Temperature of the Earth. The object of this paper 
was to explain a new and very simple formula for finding the 
mean temperature of any place in the western region of the old 
world, at all latitudes ; to point out its remarkable accordance 
with the fine series of observations collected and arranged by 
M. Humboldt. The formula given by Dr Brewster, was. 
T = 81°.5 Cos L. 
T being the temperature at the level of the sea in degrees of 
Fahrenheit’s scale, L the latitude of the place, and 8P.5 the 
mean temperature of the Equator, as deduced by Humboldt. 
This formula gives, to a surprising degree of exactness, the 
mean temperature of the parallel of 78° in the Greenland Seas, 
as ascertained from numerous observations by Mr Scoresby ; and 
from its coincidence with observations at the Equator, — in the 
parallel of 45°, — and in the Arctic Regions, there can be little 
doubt, that the mean temperature of the North Pole differs very 
little from 0° of Fahrenheit, in place of being 32°, as assumed by 
Mayer and others. The formula of Mayer errs no less than 
nine deg?res in the latitude of 78°. The paper was accompa- 
nied with a table of the ascertained Inean temperature of thirty- 
one places, compared with the new formula and that of Mayer. 
The sum of the errors of Mayer’s formula was 76°. 73, 3.0 being 
positive and 1 negative. The sum of the errors in the new 
formula was 26°.41, the positive errors being 14°.24, and the 
negative ones 12°. 17. 
Feh. 21. — Henry Mackenzie, Esq. read a continuation of 
his paper On the Dramatic Poets of Scotland. 
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