Physical Apparatus for Projection. 



191 



Mechanics. 



21.504. Plateau's Apparatus for show-ing the 

 ohlateness of a sphere of oil 



21.505. Piezometer (WeinhoUTs) 



21.506. Apparatus for demonstrating surface 

 tension 



21.507. Apparatus for capillary depression of non- 

 moistening solutions 



21.508. 5 Different Capillary Tubes 



21.509. Capillary Tubes with stand 



29,764. 2 Wide Tubes with capillary tubes com- 

 municating therewith 



29,997. Wide tube with 5 communicating capillary 

 tubes 



21.510. Capillary Tubes with plane-parallel glass 

 vessel 



21.511. Capillary Tubes alone 



21.512. Capillary Plates 



21.513. -- do., with stand 



21.514. do., larger, with adjustable angle . . 



21.515. Apparatus for showing the behaviour of 

 moistening and non-moistening liquids in 

 a conical tube 



28.688. Apparatus for showing that the issuing 

 jet consists of drops 



Wave Theory and Acoustics. 



21,510. Wave Projection Machine . 2. 



21.517. Cova's Wave Machine 2. 



21.518. Transverse Wave Machine 2. 



21.519. Apparatus for the reflection and inter- 

 ference of wave motion 1. 10. 



21.520. Adjustable Mirror and large bi-concave 

 lens for same, 2. 



21.521. 7 Tuning fork curves on stand 1. 



Optics. 



zl,522. Reusch's light-refraction Apparatus . . . 

 21,52;!. Apparatus for refraction in plane glasses 



21.524. Kaleidoscope with lens 



21.525. Total Reflection Apparatus (for showing 

 total reflection in a jet of water). . . . 



21. 525 a. do., smaller and without base . . . 



10.770. Apparatus for showing total reflection in 



glass rods 



21.526. Transparent Colour Disc 



Solar Spectrum, transparent 



21.527. Apparatus for imitating the irradiation of 

 the crescent moon 



21.528 2 Discs (Plateau's) for demonstrating 

 irradiation (for illustration see under 

 Xo. 28,903 a) 



21.529. Projection Stroboscope 



21. 529 a, 3 Extra Discs for above 



21.530. Projection Stroboscope 



21.531. Auorthoscope 



21.532. Colour circle 



21.533. Apparatus for causing ocular fatigue and 

 the successive colour contrast 



21.534. do. (Weinhold's) 



21.535. Apparatus for successive and simultaneous 

 colour- contrast . 



2 Coloured Glass Sheets for simultaneous 



contrast 



Apparatus for demonstrating the contrast 



colours as colour shadows 0. 



Projection Plates for optical illusions, 



apparently diverging, parallel lines . . . 0. 



- do., apparently bent, parallel lines. . 0. 



do., 4 right angles are apparently acute 



and obtuse in pairs 0. 



2 Plane-parallel Glass Vessels for the ob- 

 jective demonstration of the colours of 



pigment-mixtures 0. 



2 Colour Discs for the mixing of coloured 

 lights and the overlapping of transparent 



colours 1. 



Powdered Glass for colour ring? .... 0. 



Newton's Colour Eings, 70 mm diameter 0. 



do., 100 mm diameter 0. 



do., 120 mm ,, 1. 



do., 150 mm ,, 1. 



Newton's Colour Rings, with stand, ro- 

 tatory, 70 mm diameter 1. 



do., 100 mrn diameter 1. 



do., 120 mm 2. 



do., 150 mm .. 2. 



von Lommel's reflecting Stephanoscope . 0. 



do., larger 1. 



Projection-diffraction-chromosjope . . .11. 



Circular, photographic grating 0. 



Polarisation Apparatus for the whirling 



table 1. 



Weinhold Polarisation Apparatus .... 2. 



Duboscq Polarisation Apparatus .... 2. 



Polarisation Apparatus on stand .... 4. 



Simpler Polarisation Apparatus (TyndaU's) 3. 

 Reflection-Polarisation Apparatus (Grim- 



sehl's) 1. 



Demonstration Analyser (Grimsehl's) . . 1. 

 Glass Tube for polarisation experiments, 



as suggested by Grimsehl -. 1. 



s. d. 

 5. 



4. 



4. < 



4. 



15. 



5. 



4. 



12. 



18.0 



4. 



10 



12. 

 18. 



4. 

 10. 

 1.3. o 



5. 

 10. 

 10. 



8. 



0. 



15.0 



15. 



0.0 



0.0 

 12.0 



.V o 



Heat. 



s. !. 



Apparatus for showing the expansion of 



liquids 0. 1. 9 



- do., with open capillary tube .... 0. 1. 9 

 Apparatus for linear expansion of solids 2. 10. 

 Apparatus for explaining the phenomena 

 during the freezing of water and melting 



of ice, and the behaviour of water on 



boiling 0. 14. 6 



- do., without projection thermometer . 0. 10. 

 Apparatus for determining the maximum 



density of water 0. 8. 



Apparatus for proving the expansion 



anomaly of water 0. 8. 6 



Apparatus for showing circulation of water 0. 6. 

 Ruhlmann's Apparatus for the expansion 



of gases at constant pressure ...... 0. 1 1 . 



Freezing-point Thermometer 0. 6. 



Projection Thermometer 40 "to + 50 C. 0. 5. 



-idem, 10 to +160 C 0. 5. 



Projection Thermometer with long limb, 



to 30 C., graduated in tenths ... 0. 10. 



