| 摘要 |
A drawing board having a body and a generally transparent screen on the body. The screen has front and rear sides and contains a viscous opaque liquid and iron dust in the liquid. A magnetic eraser is movable within the body between a rest position away from the rear side of the screen and an operating position against that rear side for operation to move, through magnetic attraction, the iron dust away from the front side of the screen such that the iron dust becomes invisible on the screen. A spring biasses the eraser towards the rest position. A pen having a magnetic tip is used to draw on the screen.
|
