On the kinematics of a local component of the interstellar hydrogen gas possibly related to Gould's Belt.

Summary. It is shown that a local component of the interstellar neutral hydrogen displays motions characteristic for a shell or cloud expanding in the field of differential rotation. A first order model gives an expansion age of 60. 106 years. Some evidence is presented that this feature is related to the Gould Belt system of early type stars. The kinematic behaviour of this feature may be related to the spiral shock model of galactic structure. Key words: neutral hydrogen - local system - formaldehyde - Gould's Belt