Propagation of Heat in L iquids. 2 8 1 



vessel K L ; and it is placed precisely above the wooden 

 cup in the prolongation of its axis, the lower extremity 

 of the tube being at the distance of ^ of an inch above 

 the horizontal level of the brim of the cup. 



On the top of the tube of wood is placed a cylindrical 

 vessel N O, of sheet brass, 3 inches in diameter, 2} 

 inches high, which has a lateral spout, P Q, placed a 

 little above the level of its bottom. 



From the middle of the bottom of this vessel, there 

 descends a cylindrical tube of brass, 6 inches in length 

 and i inch in diameter, which ends below in a hollow 

 conical point, as represented in the figure. 



R S is a vertical and central section of a funnel of 

 brass, which ends below in a cylindrical tube of T 3 g- of an 

 inch in diameter and 6 T 6 -g- inches long. This funnel is 

 kept in its place in the axis of the cylindrical vessel 

 N O by the exact fitting of its upper edge upon that 

 of the vessel into which it is adjusted. 



The lower end of the tube of this funnel is surrounded 

 by a projecting edge or flange in the form of a hollow 

 inverted cone. The diameter of this conical projecting 

 brim above, at its base, is ^ of an inch, and it is sol- 

 dered below to the end of the tube. 



When hot water is poured into the funnel, this liquid, 

 descending by the tube of the funnel, strikes against 

 the inner surface of the hollow inverted cone which ter- 

 minates the vertical tube that belongs to the vessel 

 N O, and then, rising up through this last tube into that 

 vessel, it runs off by its spout. It was with a view to 

 force this water to come into more intimate contact with 

 the hollow cone that the projecting edge, in form of an 

 inverted cone, was added to the lower end of the tube of 

 the funnel. 



