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LXVII. Experimental Researches on the Laws of Absorption of 



Liquids by Porous Substances. By Thomas Tate, Esq. 



[Continued from p. 369.] 



THE following experiment was made to show that, at equal 

 distances from "the surface of the liquid, the rate of diffu- 

 sion is equal in all directions, that is to say, that the rate of dif- 

 fusion is independent of the force of gravity. 



Experiment IV. 

 The absorbent used in this experiment was unsized paper, 2 

 inches in width, cut longitudinally through 

 the centre to within 1 inch of the lower 

 extremity; and whilst one portion was 

 suspended vertically, the other portion 

 was bent after the manner shown in the 

 annexed diagram. Each branch was gra- 

 duated from the water-line of immersion, 

 so that the space of ascent in the follow- 

 ing Table is the distance traversed on the 

 paper measured from the level surface of 

 the water. 



It will be observed how very nearly the results in the second 

 and third columns coincide with each other, thereby establishing 

 the law above enunciated. 



The following experiment was made to test the truth of this 

 law of equal diffusion. 



Experiment V. 



The absorbent used in this experiment was unsized paper, cut 

 in the form represented in the annexed 

 diagram. The width of the portion at A 

 was as fine as possible. The paper was 

 graduated from A along the vertical line 

 A E, as well as from A along the hori- 

 zontal line B C. The ascent recorded in 

 the following Table is the vertical as well 

 as the horizontal space traversed by the 

 liquid on the paper estimated from the 



