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WOODCOCK 



[chap. 6 



In the sea these bubbles will dissolve or grow larger, depending upon their 

 size and the degree to which the water is undersaturated or supersaturated 

 with atmospheric gases (loc. cit.). However, we are not concerned here with the 

 role of the bubbles in the exchange of gases between sea and air, but in their 

 effectiveness, upon bursting, in the ejection of droplets of sea-water into the 

 overlying air. Changes in the bubble sizes below the surface are important, 

 however, for they will alter the eventual sizes of the droplets produced at the 

 surface {loc. cit.). 



DIAMETER OF BUBBLE (^i) 



Fig. 2. Droplet ejection height as a function of size of bubbles bursting in sea-water and 

 distilled water. The distilled water data are from Stuhlman (1932). 



High-speed photography of bursting bubbles has revealed something of the 

 nature of the mechanism which projects several droplets of sea-water from 

 the tip of a jet formed as the bubble cavity collapses (see Fig. 1 and Kientzler 

 et al., 1954). The relationship between bubble size, droplet-ejection height and 

 droplet size are shown in Figs. 2 and 3. In clean sea-water, free from surface 

 films, the size of the top droplet and the height to which it is thrown changes 

 very little for bubbles of nearly constant diameter. The lower drops from these 

 bubbles show greater non-uniformity, as can be seen in Figs. 2 and 3. In 



