The analysis of an eruptive prominence and disappearing quiescent filaments indicates that the prominence height on the limb increases after the filament develops a twist as seen in the Hα on the disc. The increase in prominence height, large change in the shear angle, and the appearance of filament as a U-shaped structure before the disappearance of the filament or prominence eruption can be explained by assuming that the middle portion of the filament rises above the solar surface with its edges anchored in the chromosphere. Further, the loop-like structure of the filament splits into two parts 2–3 days prior to its disappearance and the gap between the two increases with time. The increasing gap and simultaneous disappearance of both parts of the filament suggests that heating of the top of the loop-like structure begins about 2 days before its disappearance. The cause for this portion of the filament not being visible in Hα may be that it is heated to a high temperature.