NATURAL HISTORY OF SEIRORNE. 271 



Selborno stand three tenths of an inch lower than the 

 barometers at South Lambeth : whence we may conclude 

 that the former place is about three hundred feet higher than 

 the latter ; and with good reason, because the streams that 

 rise with us run into the Thames at Weybridge, and so to 

 London, Of course, therefore, there must be lower ground 

 all the way from Selborne to South Lambeth ; the distance 

 between which, all the windings and indentings of the 

 streams considered, cannot be less than a hundred miles. 



LETTER LXI. 



SINCE the weather of a district is undoubtedly part of its 

 natural history, I shall make no further apology for the 

 four following letters, which will contain many particulars 

 concerning some of the great frosts, and a few respecting 

 some very hot summers, that have distinguished themselves 

 from the rest during the course of my observations. 



As the frost in January 1768 was, for the small time 

 it lasted, the most severe that we had then known for many 

 years, and was remarkably injurious to evergreens, some 

 account of its rigour, and reason of its ravages, may be 

 useful, and not unacceptable to persons that delight in 

 planting and ornamenting ; and may particularly become a 

 work that professes never to lose sight of utility. 



For the last two or three days of the former year there 

 were considerable falls of snow, which lay deep and uniform 

 on the ground without any drifting, wrapping up the more 

 humble vegetation in perfect security. From the first day 

 to the fifth of the new year more snow succeeded ; but from 



