X.i. S4 174. 



Spark Tubes, Spectrum Tubes, Spectrum Lamps. 



515 



54173. 1:3. 54174A. 1:4. 



54 168. 1 : 3. 



54 172. 1 : 4. 



54 174 B. 1:4. 



54.161. Spectrum Tube after Geissler, Figure, thoroughly well constructed, with O, H, s. d. 

 N, CO. CO 2 , H 2 O, Cl, HC1, Br, I, Cy, HOy, NO, NO 2 , Carburetted Hydrogen; Solids: 



S, Se, Hg or Hg 2 S each 0. 3. 6 



54.162. Spectrum Tube, filled with argon (A) or helium (He) 0. 10. 



54.163. Spectrum Tube with 2 cocks, Figure, for evacuating and filling automatically 0. 5.0 



54.164. Stand for Spectrum Tubes, Figure 0. 18. 



63,071. -- idem, simpler 0.10.0 



54.165. - - idem, after Friedr. C. G. Miiller (M. T. Fig. 144) 0. 12. 



54.167. Spectrum Tube, end-on pattern, filled with O, H, N, CO, CO 2 , H 2 O, Cl, HC1, Br, I, 



Cy, HCy, NO, NO 2 , NH 3 , SO 2 , SO 3 , H 2 S, SnCl 2 , etc each 0. 5.0 



54.168. Spectrum Tube with Capillary, with Cylindrical Electrodes, Figure, for viewing 

 cnd-ori and side-on from both sides, can be supplied filled with the same gases as 



No. 54,167 0.10/0 



54.169. - - idem, filled with argon (A), helium (He) or a mixture of argon and helium | 0. 18. 



54.172. Stand with Fine Motion for Spectrum Tubes, Figure, for concentric adjustment 

 of the capillary with the spectrum apparatus, vertical fine motion by screw M, hori- 

 zontal fine motion by lever H, vertical motion by lever V 2. 0. 



54.173. Mercury Spectrum Lamp, Figure 0. 10. 



This lamp generates an intense white light well adapted for optical purposes. It is worked by 

 a not too small induction apparatus and requires no water cooling. 



The lamp is arranged so that only the cross-section of the capillary tube is utilised; the luminous 

 source then shines as a small circular spot of great intensity. 



54.174. Mercury Arc Lamp after Lummer-Straubel, Fig. A, with water box on adjustable 



stand, Fig. B 4. 0. 



The lamp requires a pressure of 25 30 volts for working; even if it can stand a considerably 

 higher voltage than this it is not advisable to go above 30 volts if the lamp lias to be durable. 



If it has only to be used for a very short time it will be sufficient simply to till the box witL 

 water; if, however, it is intended to work it for some hours the water must be made to circulate. 



54, 174 A. Spare Mercury Arc Lamp, Figure 1. 5. 



Cl. 1421, 1422, 1421 >. 1423, 1425. 

 4820,4841,1424. 33* 



