No. 54 792. 



Heat. 



567 



54 787. 1 : 6. 



54786. 1:10 



54788. 1:3. 



54 789. 1 : 3. 



54 791. 1 : 10. 



Heat. 



General. Thermal Expansion. 



52,146. Molecule Model after Korner Fig. 54 216, p. 301, for explaining heat and its gene- 

 ration by impact or friction (Fr. Phys. Techn. I, 2, Fig. 3899) 



54,785. Brass Sphere with Ring, after S'Gravesande, Figure, for showing the expansion 

 of solids by heat and contraction by cooling (W. D. Fig. 324 [306]), diameter of sphere 

 24 mm 



54,786. - - idem, larger. Figure, with sphere 75 mm diameter 



54,787. Brass Sphere on stem, Figure, with small tripod having a circular opening, for the 

 same experiment 



* 54,788. Glass Sphere with tube closed at top, for showing the expansion of liquids, Figure, 



filled with coloured petroleum (W. D. Fig. 326 [308]) 



* 54,789. Glass Sphere with Capillary Tube open at top, Figure (Gan.-Man. Fig. 462; Gan.- 



Eein. Fig. 300) 



* 54,790. - - idem, without filling, for use for demonstrating expansion of air when a mercury 



thread is introduced (Gan.-Man. Fig. 463; Gan.-Rein. Fig. 301) 



54.791. Square formed of Tubes, with two open limbs, Figure, for the expansion of liquids 



If the square of tubes is nearly filled with coloured water and one limb heated by a spirit 

 lamp the water rises in this limb. 



54.792. Air Thermoscope after Galilei (M. P., 10 th Edn., Ill, p. 6; Meyer, Naturlehre, Fig. 11) 



ci. 



s. d. 

 1.10.0 



0. 5.0 



1. 8.0 



0. 8.0 



0. 1.8 



0. 1.8 



0. 1.8 



0. 3.0 



0. 2/8 



( 'an be used with the Projection Apparatus. 



6078, 

 3410, 354, 355, 5798. 



