8 Dr Davy's Meteorological Observations. 



particularly liable to be frozen. The appearances that 

 presented in Stock-gill and Scandale-gill, the two small 

 streams in question, were remarkable and beautiful. Wher- 

 ever the banks were low, and not overhung by trees, or shel- 

 tered by great masses of rock, wherever, in fact, favourable 

 to radiation, there ground-ice was to be seen adhering to the 

 rocks and stones, and sunken entangled broken branches, 

 and often where the water was most rapid. In some places 

 there was a uniform coating of ice, but more frequently the 

 ice was in spicular crystallizations, adhering, and shooting 

 up much in the manner of a vegetable growth, — indeed, when 

 I first saw them, I took them for faded confervas." The tem- 

 perature of the stream where they were found was 32° ; — in 

 contact with them, in one or two instances that the water 

 washing them was running rather slowly, it was a little 

 lower, — a half or a quarter of a degree. In the Rotha at the 

 same time, where there was not a particle of ice excepting 

 at the entrance of these rivulets, and even there, no ground- 

 ice, the temperature was 37°. It may be deserving of men- 

 tion, that ground-ice did not appear in the lower part of the 

 Scandale rivulet, below a spot where a small stream joined 

 it from a deep field-drain, of the temperature 40°, and which 

 raised its temperature to 33°. I may mention incidentally, 

 that in one place in this latter stream, well exposed to sun- 

 shine, M'here there was much ice at the margin, and some 

 bottom ice in the middle, trouts were to be seen actively 

 swimming about in the ice cold water ; and at the same time 

 the early note of the blackbird was to be heard in an adjoin- 

 ing clump of trees, as if both fish and bird were under in- 

 fluences (probably of the bright light), independent of mere 

 temperature rousing them to exertion. 



The occurrence of ground-ice I witnessed more or less for 

 several days in the same streams and situations, — disappear- 

 ing before evening, and forming again during the clear nights, 

 — varying very much in quantity, according to the degree of 

 clearness of the night. Till the 20th, the appearances pre- 

 sented by the ice were very similar to those already described. 

 On that day, and on the following morning, a difference of 

 form was perceived. There was more smooth ice at the hot- 



