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THE CENTURY, 



same, and so by the change of the outward both the 

 glass and water will move accordingly.&quot; Pages 42-43. 

 From all that has been advanced, an impartial reader 

 must feel satisfied that there existed abundant sources 

 of popular information, highly suggestive to such an 

 inquisitive and inventive mind as the Marquis pos 

 sessed. Van Etten mentions the filling of a cannon 

 with water, the plugging it up, and exploding it by the 

 action of fire applied to its trunnion. And here John 

 Bate suggests an experimental apparatus on a small 

 scale, which the Marquis would be almost certain to 

 test, and in so doing to vary the construction and appli 

 cation. Rarefaction too is here recommended ; and the 

 effect of cooling or condensation is particularly noted, 

 the stated result being, &quot; the water will ascend&quot; We 

 can readily imagine the Marquis varying such an expe- 



