12 NATURAL HISTORY. 



off the first infusion, after a small time, and use the 

 latter. 



Experiment solitary touching the appetite of continuation 

 in liquids. 



24. Bubbles are in the form of an hemisphere ; 

 air within, and a little skin of water without : and it 

 seemeth somewhat strange, that the air should rise 

 so swiftly while it is in the water ; and when it 

 cometh to the top, should be stayed by so weak a 

 cover as that of the bubble is. But as for the swift 

 ascent of the air, while it is under the water, that is 

 a motion of percussion from the water ; which it 

 self descending driveth up the air ; and no motion 

 of levity in the air. And this Democritus called 

 &quot; motus plagae.&quot; In this common experiment, the 

 cause of the inclosure of the bubble is, for that the 

 appetite to resist separation, or discontinuance, 

 which in solid bodies is strong, is also in liquors, 

 though fainter and weaker ; as we see in this of the 

 bubble : we see it also in little glasses of spittle that 

 children make of rushes ; and in castles of bubbles, 

 which they make by blowing into water, having ob 

 tained a little degree of tenacity by mixture of soap : 

 we see it also in the stillicides of water, which if there 

 be water enough to follow, will draw themselves 

 into a small thread, because they will not discon 

 tinue ; but if there be no remedy, then they cast 

 themselves into round drops; which is the figure 

 that saveth the body most from discontinuance : the 

 same reason is of the roundness of the bubble, as 



