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Scotland , stretching from the Mull of Galloway on thesouth, to Dunnet-head on the north, between the parallels of54° 34', and 58° 42' of north latitude, may naturally be ex-pected to be a cold and bleak country. Being situated so fainorth, and a great proportion of it mountainous, its climateis very variable, and, excepting on the east coast, is general-ly moist..
With regard to the weight of the atmosphere, which isconsidered as furnishing one of the principal indications ofthe state of the weather, it is well known, that the range ofthe barometer increases as we advance from the equator to-wards the poles. It is also greater in the mountainous dis-tricts, than in the low country of Scotland . From Dr Mac-farlane’s tables of the weather, inserted at length in the Stir-lingshire Report*, and of which an extract will be found inthe Appendix , it appears that the greatest height of the ba-rometer, observed in latitude 56° 7', during a period of elevenyears, was SO-^^ inches, and the lowest 2844 i leaving arange of 2^$ inches. The observations were made at an ele-vation of about 70 feet above the level of the sea.
At Longforgan, in Perthshire, on the banks of the Tay,and probably at the elevation of only a few feet, the greatestheight observed was 30-^4 inches, and the least 284^5 l ea "ving, in like manner, a range of the barometer of 2-^s- in-ches. The period of observation was 11 years f.
The mean annual temperature of any place is also knownto depend, in a great measure, upon its latitude. Mr Kir-wan has constructed tables 4, to shew the mean annual tem-perature of different latitudes, in reference to a standard mean,which he derives from the general temperature of the Allan-
* Chap, i, Sect 3. f Statistical Account, vol, xix, p. 461.f Dr Thomson’s Chemistry, vol. iii, p. 504, 1st edit.