This paper presents a heating-capillary video-microscopy system that allows visual observation and quantification of phenomena involving biphasic dispersions with interfaces at high temperatures. The cylindrical capillaries were made to have inside diameters of similar to200 mum, while their exterior was coated with a transparent tin-doped indium oxide film that acted as an electrically heating jacket. The produced capillaries achieved temperatures ranging from ambient to at least 287 degreesC, the boiling temperature of n-hexadecane, a high boiling point hydrocarbon used in the temperature-calibration experiments. The generated temperatures may oscillate, with maximum deviations of about 3 degreesC from ambient to 80 degreesC, 9 degreesC from 80 to 170 degreesC, and 45 degreesC from 170 to 265 degreesC. In the range of 100-265 degreesC, the desired temperatures were attained at a rate from 75 to 198 degreesC/s and could be easily adjusted by changing the applied ac voltage with a variable transformer. Two examples of using the heating-capillary technique for interfacial studies at high temperatures are illustrated.