  Direct measurements of the velocity in turbulent convection of $SF_6$ near
its gas-liquid critical point by light scattering on the critical density
fluctuations were conducted. The temperature, velocity and cross frequency
power spectra in a wide range of the Rayleigh and Prandtl numbers show scaling
behaviour with indices, which are rather close to the Bolgiano-Obukhov scaling
in the wavenumber domain. The statistics of the velocity fluctuations remains
Gaussian up to the Reynolds numbers $10^5$.
