1918] 



on Studies on Liquid Films 



397 



throughout; but as the segments shrank D and d continually 

 diminished. Three illustrations of this are shown in Figs. 32-34. 

 Thej are taken from a column of six bubbles in the 200 litre globe 

 already descriljed. The four top bubbles were of equal volume, 

 while the two lowest were half the volume of the others. The third 

 segment being between two similar ones remained symmetrical to the 

 end, and thus gave more reliable results. The contraction finally 

 resulted m the column pulHng apart l)etween the fifth and sixth 

 bubbles on the 64th day. The upper five were thus left free, but 

 the oscillations were so persistent that only a blurred photograph was 

 possible ; this was, however, sufficient to give some measures of the 

 free segments for comparison with those obtained when strained. 

 Fig. 32 was taken at the stare, Fig. 33 on the 16th day, and Fig. 34 

 on the 64th day before partition took place. 



The volumes and surfaces for the third segment selected for cal- 

 culation were as follows (Table II.) :— 



Black Six-BuhhU Chain. 



Table II. 

 Dimensions of Segment (3). 



Table III. 

 Air Transfer through Segment (3). 



