392 NATURAL HISTORY 



LETTER LXIII. 



TO THE SAME. 



As the frost in December, 3784, was very extraordi- 

 nary, you, I trust, will not be displeased to hear the 

 particulars ; and especially when I promise to say no 

 more about the severities of winter after I have finished 

 this letter. 



The first week in December was very wet, with the 

 barometer very low. On the 7th, with the barometer 

 at 28 five tenths, came on a vast snow, which con- 

 tinued all that day and the next, and most part of the 

 following night ; so that by the morning of the 9th the 

 works of men were quite overwhelmed, the lanes filled 

 so as to be impassable, and the ground covered twelve 

 or fifteen inches without any drifting. In the evening 

 of the 9th the air began to be so very sharp that we 

 thought it would be curious to attend to the motions of 

 a thermometer : we therefore hung out two ; one made 

 by Martin and one by Dollond, which soon began to 

 show us what we were to expect; for, by ten o'clock, 

 they fell to 21, and at eleven to 4, when we went to 

 bed. On the 10th, in the morning, the quicksilver 

 of Dollond's glass was down to half a degree below 

 zero; and that of Martin's, which was absurdly gra- 

 duated only to four degrees above zero, sunk quite 

 into the brass guard of the ball; so that when the 

 weather became most interesting, this was useless. On 

 the 10th, at eleven at night, though the air was perfectly 

 still, Dolloud's glass went down to one degree below 

 zero ! This strange severity of the weather made me 

 very desirous to know what degree of cold there might 

 be in such an exalted and near situation as Newton. 

 We had, therefore, on the morning of the 10th, written to 

 Mr. , and entreated him to hang out his therino- 



