250 



Measurement of Time. - Introduction to Physics. 



Xo. r.1739 



51 744. 1 : 5. 



51 746. 1 : 5. 



51 749. 1 : 3. 



51 751. 1 : 5. 



51.739. Switch for putting the chronographs in and out of circuit from a distance. s ll 



Extra Price 7. 5. o 



51.740. Other lengths of seconds from 5 to 100 mm, as desired. Extra Price 1. 10. to 8. 15. 



51.741. Device for two different lengths of seconds Extra Price 11. 10. 



51.742. --idem, for 3 lengths of seconds Extra Price 14. 5. 



51.743. Reading Machine (Oppolzer's) for strip chronographs (cf. Figure 51,744), con- 

 sisting of a system of hairs and levers forming a parallelogram 17.10.0 



51.744. - - idem, with Seconds and Minutes Counter, Figure 29. 0. 



51.745. Reading Glass with finely diverging lines, in case 2. 0. 



Introduction to Physics. 



51.746. Displacing Cylinder for determining the Specific Gravity, Figure, with lateral s '' 

 eduction pipe (W. D., Fig. 57 [52]) 0. 5. n 



51.747. Displacing Vessel (F. C. G. Muller's) (M. T., Fig. 68) 0. 6. 



:!.74. Overflow Vessel (Grimsehl's) for volume determinations 0.1.0 



51,749. Pycnometer, Figure, with lid ground on, pipette and tripod (W. D., Figs. 58 



and 59 [53 and 54]j, without measuring glass 0. 3. 



* :. 1 .7:.o. Disc with hole and glass lid, for showing the divisibility of fuchsia (\V. I)., Fig. 56 [51]) 0. 2. 



51.751. Double Bulb on stand, Figure, for explaining the expansion of gases by means 



of red nitrogen peroxide gas (W. D., Fig. 60 [55]), with 2 taps and 1 glass stopper 0. 10. 



51.752. idem, without stand 0. 7. 



Can be used with the projection apparatus. 



Cl. 



. 

 447, 41*, :KO. 



