Dust shells around certain early-Type stars with emission lines

The results of an investigation of circwnstellar dust shells around 22 early- type stars with emission lines are given. The absorption at 1640 Å, the linear sizes, and the masses of the dust shells were determined. They differ from one another (see Table 1). In determining the mass of a shell, the radius of the H II zone was taken into account, where the average electron density in the gaseous shell was taken to be ne = 2.5·105 cm-3.