磨齿

磨 = 石 + 麻 : Mahatma Gandhi (m) has been tied down in the observatory's kitchen (o2) with ropes made of hemp (麻). He uses a stone (石) to patiently rub (磨) through the ropes.

齿 = 止 + 凵 + 人 : Charlie Chaplin (ch) has an aching tooth (齿), and Neanderthal Man (人) is about to help him take it out using an electrical barrier (止) in the space station (Ø3). They attached the barrier to the tooth and as Neanderthal Man will plug it into the receptacle (凵), the barrier will pull out the tooth.