Page:Transactions of the Natural History Society of Northumberland, Durham, and Newcastle-upon-Tyne 1838 Vol.2.djvu/148

138 and many of them rare, notwithstanding none of its mountains reach the height of three thousand feet, for it is at a superior elevation

At Edinburgh, lat. 55° 47', mean temperature, 47° 8'. This calculation has been made from six years' excellent observations, by Professor P LAYFAIR ; during this time, the thermometer was never seen above 75° 8'. Vegetation continues from March 20, to Oct. 20. The mean temperature of these seven months is, from 55° 8' to 50° 9'; accordingly, the years are more or less fruitful; wheat does not ripen if the mean temperature descends to 47° 6'. The mean heat of the summers of Scotland in the environs of Edinburgh, is found again on the table lands of New Grenada, so rich in wheat, at 1,400 toises of elevation, and at 4° of north latitude.—Humboldt.

The range of temperature of the springs in the neighbourhood of Newcastle has been, for the preceding twelve months, from 42° to 49½°. Those which appear most regular are, the Cradle Well, by the road to Jesmond, and the Holy Well, in Jesmond Dene, the courses of which must be in the Seventy-fathom Post, as the miners call it. This stratum of Sandstone is nearly 50 feet thick, and crops out on the south-west side of the Town Moor, covering the high main seam of Coal, which has been worked out from under the springs; and as the old colliery is now drained, the water cannot rise from below the Coal.

During the month of April, 1818, the Jesmond Springs, stood at 42°

On the 19th of May, 44

On the 1st of June, 46

On the 10th of June, 47

On the 15th of July, 48

On the 28th of ditto, 49

On the 6th of September, 49½

On the 1st of November, 49

On the 15th of ditto, 48

On the 15th of December, 45

On the 17th of January, 44

On the 27th of ditto, 43

On the 5th of March, 42

Mean temperature, ascertained by fifty observations, 45¾°.

From a spring rising in the higher part of Newcastle, at an elevation of 180 feet above the level of the sea, the following less correct results were obtained, owing to its flowing for some distance nearer the surface of the earth :—

During the month of April, 1818, the temperature was 42°

On the 19th of May, 46

On the 1st of June, 48

On the 10th of ditto, 50

On the 15th of July, 52

On the 28th of ditto, 54

On the 6th of September, 56

On the 1st of November, 53

On the 15th of ditto, 51

On the 15th of December, 47

On the 17th of January, 44

On the 27th of ditto, 43

On the 5th of March, 42

Mean temperature, 49°. ''W INCH on the Geographical Distribution of Plants through the Counties of Northumberland, Cumberland, and Durham. — Pamphlet, 8vo., 2d Edition'', 1825.