ERRATA. 



Page 39 line 24, for he detailed. On their return, read, he detailed 



on his return. 



251 line 3, for different densities, read, the same densities. 

 259 last line but 3, instead of combination, read, combustion. 

 268 for devallate, read, devellate. 

 274 last line but 5, for force without power, read, inertness 



without power. 



375 last line but 2, for of was effected, read, as was effected. 

 402 line 5, for have concord, read, have conceived. 



