C A PILLAR Y A TTRA CTION. 1 5 



same, and my metrical sense of touch has merely 

 told me, in this particular sense, what we all know 

 theoretically must be true in every case of pro- 

 ceeding by different ways to the same end from 

 the same beginning. 



Now in this second way we have, in performing 

 the folding motion, allowed the water surface to 

 become less by sixty square centimetres. It is 

 easily seen that, provided the radius of curvature 

 in every part of the surface exceeds one or two 

 hundred times the extent of distance to which the 

 molecular attraction is sensible, or, as we may say 

 practically, provided the radius of curvature is 

 everywhere greater than 5,000 micro-millimetres 

 (that is, the two-hundredth of a millimetre), we 

 should have obtained this amount of work with 

 the same diminution of water-surface, however per- 

 formed. Hence our result is that we have found 

 4*5/60 (or 3/40) of a centimetre-gramme of work 

 per square centimetre of diminution of surface. 

 This is precisely the result we should have had if 

 the water had been absolutely deprived of the 

 attractive force between water and water, and its 



