Abstract: Surface tension driven flow in high temperature oxide melt was visualized by means of the already proved method of high temperature in situ optical
observation. The streamlines of the steady thermocapillary convection were marked in the form of an axially symmetric pattern. The oscillation motion
of thermocapillary vortex was observed accompanied by synchronous temperature oscillations. Another type of oscillation thermocapillary convection was also
observed mainly caused by the variation of the curvature of meniscus of the melt free surface. Finally the oscillatory frequency of the convection against
the temperature of the melt was measured.

Key words: surface tension driven flow, oxidemelt, in situ observation