On Juration and Repulfton. lai 



paper was lighted, and burning up to the gun- 

 powder during its afcent, it exploded, and at 

 rhe fame inftant fired the inflammable air. 



Two corks, or other light bodies, fwimming 

 on water, and having been previoufly moiftened, 

 feem to attradt each other. The fame thing hap- 

 pens if they are not moiftened, but they deprefs 

 the furface of the water by lying upon it when the 

 water does not wholly adhere to them : but if 

 one be moift and the other dry, they recede from 

 each other J and if a dry one be driven againft 

 the fide of the veffel containing the water, it is 

 repelled in a manner very much refembling the 

 reaftion of elaftic bodies. In both the cafes 

 where the corks approach towards each other, 

 the furface of the water is raifed or depreffed 

 by the adhefion of a circle of water to the cork, 

 which alfo attrafts other particles till the gravi- 

 tation and cohefion are equally balanced as in 

 capillary tubes j and when thefe circles of at- 

 tracted water meet, and that in parallel fitua- 

 tions, they attract each other, and uniting, en- 

 deavour to form one circle, as two bubbles or 

 drops of water unite and form one larger.; this 

 brings the corks together, which would alfo 

 unite and form one larger cork were they not 

 prevented by the ftrength of cohefion between 

 their own particles. But when one raifes and 

 the other depreffes-the water, each cork attrads 



its 



