i88 ESSAYS AND OBSERVATIONS 



fafely conclude, that the lofs in his experi^ 

 rnent was proportional, and proceeded chiefly 

 froni the diffipation of fixed air. 



According to our theory, the relation of 

 the calcarious earth to air and water appeared 

 to agree with the relation of the fame earth 

 to thp vitriolic and vegetable acids. As 

 chalk for inftance has a ftronger attraction 

 for the vitriolic than for the vegetable acid, 

 and is diffolved with nmore difficulty when 

 combined with the firft, than when joined to 

 the fecond ; fo it alfo attracts air more 

 flrongly than water, and is diflblved with 

 more difficulty when faturated with air than 

 when compounded with water only. 



A calcarious earth deprived of its air, or 

 m the ftate of quick-lime, greedily abforbs a 

 confiderable quantity of water, becomes fo- 

 Ui,ble in that fluid, and is then faid to be 

 flaked ; but as foon as it meets with fixed 

 air, it is fuppofed to quit the water and join 

 itfelf to the air, for which it has a fuperior 

 attraction , and is therefore reftiored to its 

 firfl: fl:ate of n^ildnefs and infolubility in 

 water. 



When flaked lime is mixed with water, 

 the fixed air in the water is attradted by 



the 



