58 On the Friction of Water, §c. [Nov. 18, 



portional are almost exactly the same for similar surfaces, in these 

 experiments, as in Mr. Fronde's experiments. 



(6.) A series of experiments were made on the influence of the 

 temperature of the water on the friction, and the author is not aware 

 that any direct experiments on fluid friction, at different temperatures, 

 have previously been made. The experiments show that the friction 

 diminishes rapidly with increase of temperature. The alteration is so 

 great that even five degrees variation of temperature alters the friction 

 by about one per cent. 



(7.) "When the viscidity of the fluid was increased by dissolving 

 half a hundredweight of sugar in the water of the cistern, the f rictional 

 resistance of the disk was increased. But the proportionate increase 

 of resistance was much less than that observed by Coulomb, in a similar 

 experiment at a very low velocity. 



At the close of the Meeting Professor Graham Bell made experi- 

 ments with his Photophone. 



