Page:Transactions of the Natural History Society of Northumberland, Durham, and Newcastle-upon-Tyne (1867).djvu/72

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54
A NEW FLORA OF

This shows us clearly what an immense power the direct influence of the sun exerts, and consequently how different is the position with regard to temperature of a sheltered and unsheltered station.

Extreme Degrees of Temperature.—We have spoken as yet altogether of average monthly temperatures, but in connection with our present inquiry, single extreme temperatures, and especially extreme minima, must not be altogether passed over. It will, of course, be gathered, from what has been already said, that extremes in each direction are much smaller in England than on the Continent. The most striking point about the extreme degrees (and this applies particularly to minima) is, how much smaller they are near the sea than in the interior. In England, in very cold weather, the extreme degrees are just as likely to run from north to south as from east to west, so that there is no decided and uniform advantage between say the upper part of the course of the Thames over Tynedale. The part of England which has the decided advantage in this respect is the south-west, and even on the coast the extremes are much smaller on the west than on the east. If we compare an extreme summer with an extreme winter, the result will usually be something like the following:—

MAXIMUM AND MINIMUM TEMPERATURES IN THE SHADE.

LOCALITY. Maximum in the month of July, 1859. Minimum on the night of Dec. 25, 26. 1860. Difference between the two.




Helston 90 32 58
Ventnor 79 24 55
Greenwich 93 8 85
Derby 83 2 81
Nottingham 89.5 —8 97½
Liverpool 82 16 66
Manchester 85 —3 88
Wakefield 90 -2 92
Leeds 90 6 84
York 82 —4 86
Scarbro' 77.5 16 61½
Allenheads 79 8.3 70.7
Bywell 85½ 82
North Shields 81.4 6.8 74.6