NIL .V>490. 



Bottom Pressure. Hydrostatic Paradox. 



341 



\ 



52 487. 1 : 0. 



52 488. 1 : 6. 



52 489 A. 



52 489 B. 



52 489 C. 1:8. 



5g 490. 1 : 7. 



special scale is provided for showing the level of the liquid. The different annexes have conical brass s. d. 

 mounts and can therefore easily be interchanged. The apparatus has a lateral annex-tube so as to 

 be able to connect it with another vessel. 



The piston packing is of mercury; the regulating screw fitted at the top of the apparatus should 

 be turned in order to bring the pointer to zero. 



52.488. Haldat's Apparatus, for showing that the pressure of liquids depends on their height 

 and the surface of the bottom of the columns and not upon the capacities of the vessels, 

 Figure, with 4 different tubes 2. 10. 



52.489. Hartwich's Apparatus for the Hydrostatic Paradox, Figs. A, B and C (Ztschr. f. d. 



phys. u. chem. U. 16, 1903, p. 275), consisting of 3 single pieces of apparatus ... 4. 0. 



If the vessels are filled with water, the vessel A is lifted up by buoyancy, vessel B sinks on 

 account of the action of bottom pressure, while the cylindrical vessel, Fig. C, remains motionless as 

 neither pressure at base nor buoyancy bring any action to bear on this. 



52.490. Sire's Apparatus, Figure, for showing the Hydrostatic Paradox, with 2 connecting 



cocks and 1 discharge cock 2. 10. 



The following can be shown by the apparatus: (1) that the pressure at the base is independent 

 of the quantity of liquid; (2) that the pressure at base depends on the extent of surface at base and 

 on the level of the liquid; and (3) that this pressure is equal to the weight of a column of liquid 

 whose base is the compressed surface and whose height is the height of compression. 



Cl. 721, 722, 



726, 5824. 



