REPORT ON CAPILLARY ATTRACTION. 



SJ79 



surface. The diameter of the tube was in each case l""' -29441.*, 

 or in English measure, '05096 of an inch. 



2 



Mi.mi. 

 30-2621 



Sq. Inch. 

 = -0469 



= 12-1649 = -0188 



= 13-1606 = -0204 



For water, . . 



For alcohol, sp. gr.\_2 

 •81961, ..../« 

 For oil of turpentine,"! ^ 

 sp. gr. -86946, . ./"^ 

 By means of these values the weights of the columns of fluid 

 raised by a disc of white glass, 118"''-366, or 4-66 inches 

 in diameter, just when the fluid detaches itself from the disc, 

 are determined by the theory to be respectively 



Grammes. Grammes. Grammes. 



59-5873 31-1435 34-350, 



and the experimental determinations t are. 



Grammes. Grammes. Grammes. 



59-40 31-08 34-104. 



The nearness of these to the theoretical results not only con- 

 firms the theory, but shows also the correctness of the values 



2 

 of — deduced from the experiments on capillary tubes. Dif- 

 ferent experimenters | have determined differently the heights of 



• The '"'• attached stands for millimetre, and mi-mi- foj- square millimetre. 



f These weights expressed in English grains are respectively 917"14, 

 479'87, and 526'56, which being divided by the number of square inches in 

 the surface of the disc, give 53 J grains con-esponding to each square inch for 

 water, 28 gi-ains for alcohol, and 31 grains for oil of turpentine. Achard obtains 

 for water 39^ grains, for alcohol 23-4 grains: Dutour finds 44"1 grains, and 

 25-6 grains. In the experiment of Taylor {Phil. Tram. 1721) on the attrac- 

 tion of wood to water, the raising force was 50 grains to each square inch. 



X The following Table is given in the Art. Capillary Attraction of the Edinh. 

 Encycl. : the heights are reduced to a tube whose diameter is -01 of an inch. 



The experiments of Sir David Brewster were made with much care, and em- 



