1^8 NATURAL HISTORY 



Valence, The tube was first filled here (at 

 Selhorne ) twice with care, when the mer- 

 cury agreed and stood exactly with my own ; 

 but being filled again twice at Newton, the 

 mercury stood, on account of the great 

 elevation of that house, three-tenths of an 

 inch lower than the barometers at this vil- 

 lage, and so continues to do, b^ the weight 

 of the atmosphere what it may. The plate 

 of the barometer at Newton is figured as 

 low as 27 ; because in stormy weather the 

 mercury there will sometimes descend be- 

 low 28. We have supposed Newton-house 

 to stand two hundred feet higher than this 

 house : but if the rule holds good, which 

 says that mercury in a barometer sinks one- 

 tenth of an inch for every hundred feet 

 elevation, then the Newton barometer, by 

 standing three-tenths lower than that of 

 Selborne, proves that Newton-house must be 

 three hundred feet higher than that in 

 which I am writing, instead of two hun- 

 dred. 



It may not be impertinent to add, that 

 the barometers at Selborne stand three- 



