CONTENTS. V 



Page 

 CHAPTER XI. 



On the Gravity and Levity of Solids, and 

 of Liquids %Q9 



CHAPTER XIT; 

 On the Gravity and Levity of Gases 248 



CHAPTER XIII. 



On the Nature of Expansibility of Elasti* 

 city of Flexibility of Mobility and of 

 Immobility ; and the difference which ex- 

 ists in the nature of each 2&7 



CHAPTER XIV* 



On the relation which exists between the 

 expansible power of Gaseous Bodies, 

 and the Resistance they are able to over- 

 come 271 



CHAPTER xv. 



On the Inequality of Pressure produced by 

 expansible Bodies, when the equilibrium 

 is destroyed. In this Chapter it is shown 

 that the Elevation of the Mercury in thf 

 Torricellian tube, is not caused by the 

 Weight, but by the expansible Force of 



