256 CAPILLARY ATTRACTION. 



2. That it rises to the same height in vacuo, as 

 in atmospheric air. 



3. That the velocity and elevation to which 

 water ascends in capillary glass tubes, cceteris 

 paribus, is inversely as their diameters. 



4. That the upper surface of water, spirit of 

 wine, and various other liquids, in capillary glass 

 tubes, was concave ; which he rightly attributed 

 to a stronger attraction of the particles of water 

 in immediate contact with the glass for it, than 

 for each other. 



In 1805, Dr. Young read a paper before the 

 Royal Society on the cohesion of fluids, in which 

 he reduced all the phenomena to the joint agency 

 of a cohesive and repulsive force, which in fluids, 

 he thought balanced each other. But as he does 

 not explain what causes the particles of liquids 

 to approach or recede from each other, his whole 

 theory is vague, and very difficult to compre- 

 hend. - 



The following passage taken from a paper on 

 capillary attraction, by Professor Sang of Edin- 

 burgh, may be regarded as a specimen of the 

 obscure manner in which this interesting subject 

 has been generally treated ; and of the prevalent 

 opinion in regard to the recondite nature of the 

 cause which determines the attraction between 

 liquids and solids. He observes, that " the whole 

 of the phenomena are due to a change in the 

 corpuscular arrangement produced by the simple 



