4 Dr Davy's Meteorological Observations. 



monly between 50° and 45° ; the streams were about 6° 

 higher than in the preceding October ; and only on one night 

 was there hoar-frost, that of the 1st. The weather, except- 

 ing this last mentioned night, was almost uninterruptedly 

 gloomy ; there were only four days in which there were par- 

 tial gleams of sunshine ; and it was almost uninterruptedly 

 calm ; and the little wind that there was, was chiefly from 

 the W. and SW. The last December was unusually cold ; 

 frost set in on the 5th, and continued with little interruption 

 the whole month ; without snow, and with little or no wind, 

 and a good part of the time with a clear atmosphere ; hoar- 

 frost appearing not only at night frequently, but often con- 

 tinuing and increasing in the shade by day, and that some- 

 times so copiously, as to have the appearance of a fall of 

 snow. I may mention another instance, displaying the same 

 effect in the course of a very few hours. On the 30th of 

 March, at 1 A.M., with a clear calm atmosphere, a thermo- 

 meter placed on the grass, on which was hoar-frost, fell from 

 34° (which it was when suspended in the air above the spot) 

 to 28° ; seven hours later, when the sky had become obscured 

 by mist, and a very fine rain Avas falling, so small as hardly 

 to be visible, the thermometer in the same situation shewed 

 that the grass had become as many degrees warmer than 

 the air as before it was colder ; on the grass it now stood 

 at 44°, in the air at 38°. 



The observations I have given show, that almost through- 

 out the year, hardly a month excepted, the temperature here, 

 in connection with radiation, is occasionally reduced to or 

 below the freezing point. And this is in accordance with 

 the common experience of the natives, the best informed and 

 most observant of whom have told me, that hoar-frost (the 

 criterion of such a reduction of temperature) is not unusual 

 even in the height of summer in fine weather. 



A marked peculiarity of the climate of the lake district is, 

 that whilst the range of the thermometer throughout the 

 year is not great, — less, I believe, than in London or in the 

 midland counties, — the daily vicissitudes are considerable, 

 owing very much to the sudden changes of atmosphere, pro- 

 moting or preventing radiation. One hour, under a screen- 



