938 



Voltaic Electricity. Section 4: Ohm's, Kirchhofi's and Joule's Laws. 



NIL I!'.' 129 



62134. 1:5. 



62 131. 1 : !). 



62,129. Apparatus after I'ensder, F i g u r e, for showing the mode of action of heavy current 

 fuses (Ztschr. f. d. phys. u. chem. U. 16, p. 84), with 3 glow lamps with fuses for the 

 single lamps and for the groups 2. 10. o 



:>3,os2. Apparatus for Demonstrating the Arc in Vacuo, Figure, tubulated receiver with 



carbon holders and clamps 1. 12.0 



62.131. Carbon Clamps as suggested by Dr. Uriisch (Liibeek), with 1 thick carbon and 1 carbon 

 crucible, for use as electrical assay furnace, Figure, without the Runsen stand 

 illustrated .' I. 12. o 



62.132. Extra Carbons for above Kadi o. 0.3 



62.133. Spare Carbon Crucible for above Kadi o. o. 6 



<;_>. l.'M. Demonstration Electric Melting Furnace for 20 30 amperes, Figu re, with horse 



shoe magnet; without melting crucible and protecting screen 7.10.0 



The furnace is of iron with an inner clay lining- A fire-proof block provided with an adjusting screw 

 can be moved up and down on the health of the furnace. This hearth block carries the small crucible, 

 which is made of graphite, lime, niagnesite. etc. according to the operation to be carried out. The carbon 

 electrodes, to which the current is conducted, project into the crucible. The furnace space is closed off 

 by mica plates back and front, thus allowing the inside of the furnace and also the process of melting 

 to be observed. By fixing a powerful magnet, as shown in the figure, the arc can he made to take the 

 shape of a pointed flame The furnace is intended for 20 .'id amps, and ."ill ~ volts. The carbons are 

 HI mm in diameter 



cl. >:,:',, sisii. f-'s. 

 3529, 521IO. 



