Operation of the Fisher-Johns Apparatus

Line Cord (at the back). Brings a.c. power to unit. Should be plugged into a live wall socket. 

Fuse (also at the back). Provides electrical protection for the unit. 

Voltage control. Controls the rate of heating, not the temperature The higher the setting, the faster the temperature rise. 

Thermometer end cap. Keeps thermometer from falling out. If the cap becomes loose, the thermometer tends to go belly-up, and the markings turn over. Don t try to fix this while the unit is hot. Let it cool so you won t get burned. 

The hot stage. This is the heating block that samples are melted on. 

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