They are the transparent pipe and some text on the tube (the text part is based on the radiation poem I created). I used ink and carbon pen marker for the painting part, borrowing the water-absorbing

properties of wood, which can be smeared on t

he polished wooden board On.

There is a power wheel on the back of the top mechanical machine, which gives rotation. The white one is a wound cotton thread. For details of the video, see the link on the webpage.