We comment on the new astrometric results of our monitoring of visual double stars. Our results contain more than 400 visual binaries and they are based on our recent CCD observations. The targets are distributed on both hemispheres. Existing data bases of visual double stars contain optical as well as physical pairs. Statistical studies of relative proper motions of the components of double star are based on a sample of astrometric measurements. Such studies are an accurate tool for the extraction of the astrophysically interesting common origin (physical) pairs. Astrometric monitoring of visual double stars provide data which are necessary for such studies. As a by-product of our work we present an accurate determination of the scale of the 1m telescope of the South African Astronomical Observatory.