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ADOLF F. VOIGT 



lugs are cemented glass bulbs that can be filled with a drying agent. 

 By means of rectangular retaining rims, made of }/^ in. sheet alu- 

 minum, aluminum foil windows of any desired thickness can be held 

 securely on the top and bottom of the case (see Figs. 4 and 5). The 

 system can be made fairly impervious to air by applying a soft wax 



Wooden box 





Voltage control for 

 electroscope fiber 



Switch 



Wooden light 

 support — -) 



110 V. G.c. input 



Fig. 5. Lauritsen electroscope assembly. 



{e.g., Apiezon) at the places where joints are made and cementing the 

 aluminum windows in place with Duco cement. 



As support for this chamber, two vertical aluminum plates are 

 made from 3^ X 3 in. strips long enough to reach the level of the table. 

 Grooves machined in these plates allow an adjustable shelf to be 



