No. 54 829. 



Dilatometers. Expansion Anomaly of Water. 



573 



54825. 1:3. 



54827. 1:5. 



52549. 1 : 5. 



54.823. Glass Cylinder with Heating Device, Figure. (1) for investigating the stratifi- 

 cation of liquid masses in accordance with their specific gravity; (2) the circulation of 

 water, in which the thermometer shows a lower temperature in spite of its proximity 

 to the thermal source; (3) convection of water. With two thermometers 



54.824. Glass Cylinder with Cooling Ring, after Hope, Figure, for investigating the strati- 

 fication of aqueous masses according to their specific gravity and for determining 

 maximum density (Gan.-Man., Fig. 478; Gan.-Eein., Fig. 323), for cooling by ice . . 



54.825. 2 Thermometers with annular, horizontally arranged Vessels, after Weinhold, Figure, 

 for measuring the temperature-differences in different layers of water, particularly also 

 for measuring the temperature in the lower aqueous layers of a vessel on reaching maxi- 

 mum density (\V. D., 4 th Edn., Fig. 339) 



The attainment of maximum density is determined by the Looser or Kolbe Thermoscope (or in 

 another manner, e. g. with Weinhold's Apparatus No. 54,826) and the temperature measured in the 

 undermost and uppermost aqueous layers. 



The thermometer intended for the lower aqueous layer has a capillary tube 20 cm long beetween 

 vessel and scale in order that the readings of the instrument may not be appreciably influenced by the 

 temperature of the upper aqueous layers. The thermometers are alcohol-filled, 1" = 5 mm length. 



54,826. Thermoscope after Weinhold, 

 Water (W. D., 2 nd Edn., p. 304) 



Figure, for 'measuring the maximum Density of 



* .VI, 827. Apparatus after Wais, Figure, for shewing the Expansion Anomaly of Water by 

 cooling by means of ether evaporation; wide test tube with water thermoscope, inlet 

 and outlet tube for gas or air blowing, and piece inserted having narrow test tube. Can 

 be used with the Projection Apparatus (Ztschr. f. d. phys. u. chem. U. 13, 1900, p. 219) 



52,549. Hydrometer, very sensitive, F i g u r e, for measuring the Density of Water at tem- 

 peratures between and 25 C. and for proving Maximum Density: large pattern . 



Cold-water Floats: see Nos. .->:>, 526 and 52,528, p. 345. 



:>I.X29. Lantern Slide of the curve of maximum density of water in relation to that of glass 



(W. D., Fig. 340 [320]) 



s. d. 



1. 4.0 



0.16.0 



1. 5.0 



0. 6.0 



0. 8.0 



0.15.0 



0. 1.6 



* Can be used with the Projection Apparatus. 



Cl. 6144. 



3753, 1884, 359, 787. 



