PURPOSE: To prevent the deposition of stuff on liquid surface by providing the main body upper part with a glass stuff supply inlet and a waste liquid supply inlet so as to communicate from the outside to the storage space of a melting pot main body.

CONSTITUTION: At the top of the melting pot main body 1, a stuff supply inlet 19 and a waste liquid supply inlet 20 and a glass exit 7 are provided so as to communicate from the outside to a storage space 5. Liquid glass 15 is stored in the space 5, specific electric current is sent between two electrodes 14 to heat the glass and maintain and waste liquid 11 is supplied in the space from the supply inlet 20 and mixed with glass 15. Gas 13 generated in the space 5 is sent from the exit 7 to a gas processor to process. By connecting a liquid glass exit 16 at the lower part of the main body 1 to a glass solid vessel and opening a switch valve 17, glass 15 is supplied to the glass solid vessel. After charging a specified amount, the switch valve 17 is closed and the solid vessel is removed naturally cooled and solidified. As the glass stuff 10 and waste liquid 11 are individually supplied to the specific part in the space 5, no piled layer of the stuff 10 is formed on the glass stuff surface and thus liquidation is not disturbed.