Measurement and control instruments and apparatus for the metallurgical industry (and for liquid glass), namely, immersion probes and related measurement instruments in the nature of indicators and analytical instruments for the analysis of molten metals and slag (or liquid glass); immersion probes and measuring instruments, namely, sampling probes to determine the gas and carbon levels in molten metals and slag (and for liquid glass); temperature measuring instruments and equipment, namely, temperature probes, thermocouples, temperature displays and related temperature measurement instruments