[ 3oO 



follows: I**, that the Ja^fie ratio, or hygrornetrical Segree, will in- 

 dicate a different faturating quantity, and a difFerent abfolute 

 quantity of njoiflure, in every difFcFent degree of tenaperature. 



sd''. That if in a given JJ rattan of air the temperature be 

 altered, while the quantity of moiftur« remains conftant, the ratio 

 or degree will alfo be altered ; becaufe the quantity necefTiry 

 to faturation is altered: therefore, if in this cafe the temperature 

 be raifed, the index wnW be lowered, and mark a greater drynefs, 

 becaufe the air is farther from faturation, and therefore relatively 

 dryer; and, vi'ccverfa, if the temperature be lowered, the index 

 will afcend, and mark a greater degree of moifture, though its 

 real quantity be the fame, becaufe the air is then nearer to the 

 point of faturation than it was before. 



This ratio of the adual degree to the faturating quantity is 

 ■what I call the rtlditwe faturability of air. 



Hence it follows that, at high temperatures, the fame hygro- 

 metrical degree denotes an abfolute quantity of moifture far 

 greater than it does at low temperatures; becaufe, though the 

 ratios to the faturating quantity are nearly the fame, yet the fatu- 

 rating quantity in high temperatures is far greater than in low 

 temperatures, and a high hygrometrical degree in air at a /owtempe- 

 VoL. Vill. Pp rature 



