CAPILLAR Y A TTRA CTION. 1 1 



grammes weight, before they come into absolute 

 contact. I am supposing the area of each of the 

 opposed surfaces to be a few square centimetres. 

 To fix the ideas, I shall suppose it to be exactly 

 thirty square centimetres. If my sense of force 

 were sufficiently metrical, I should find that the 

 work done by the attraction of the rigidified 

 pieces of water in pulling my two hands together, 

 was just about four and a half centimetre- 

 grammes. The force to do this work, if it had 

 been uniform throughout the space of fifty micro- 

 millimetres (five-millionths of a centimetre) must 

 have been nine hundred thousand grammes 

 weight, that is to say, nine-tenths of a ton. But 

 in reality it is done by a force increasing from 

 something very small at the distance of fifty 

 micro-millimetres to some unknown greatest 

 amount. It may reach a maximum before 

 absolute contact, and then begin to diminish, or 

 it may increase and increase up to contact, we 

 cannot tell which. Whatever may be the law of 

 variation of the force, it is certain that through- 

 out a small part of the distance it is considerably 



