No. 53301. 



Chemical Harmonicas (Singing Flames). Rotating Mirrors. 



431 



61 490. 1 : 10. 



61 494. 1 : 8. 



53 297. 1 = 6. 



53 298. 1 : 5. 



61491. 1:7. 



53 301. 1 : 7. 



52,031. Rotating Mirror Box (Cube Mirror), F i g. 52,031, p. 284, with mirrors 12 cm length 

 and width, for placing on the whirling table, for demonstrating the flame images . . 



61,490. --idem, with toothed-wheel drive, Figure 



61,494. - - idem, with clockwork which can be regulated, Figure 



The speed can be regulated within very wide limits. 



53.297. - - idem, with Electric Motor Drive, Figure, for connecting up to 2 volts and 

 8 amperes Direct Current 



The electric motor can be used also for explaining Ritchie's Top. 



53.298. Rotating Mirror Box, larger, Figure, on stand, with mirror of 20 cm height and 

 12 cm width, for hand or cord drive 



61,491. - - idem, driven by 110 volts Direct Current Motor, .Figure 



If the motor is required for a different kind of current or voltage the price is altered accor- 

 dingly. 



61,493. - - idem, with Alternating Current Synchronous Motor 



When ordering, the network voltage and frequency (number of pole-changes per second) should 

 be quoted. 



52,032. Rotating Mirror, after Eeichert, with circular mirror set obliquely; for placing on 

 the whirling table (M. P. I, Fig. 648 [675]) 



53,301. --idem, on stand, with clockwork, Figure 



Cl. 6029, 380, 

 1074, 3368, 



8. d. 



0. 13. 

 2. 10. 

 5. 10. 



2. 4.0 



1. 0.0 

 6.10.0 



7. 0.0 



0. 16. 

 2. 14. 



1075, 

 5550. 



