Helga Horse (hu) is reading the little red book (红) in the engine's kitchen ((e)ng2), when she discovers that it is being eaten by a silk worm (纟). She overreacts a little and wants to beat the silk worm with a steel beam (工).
尘
=
土
+
小
:
Charlie Chaplin (ch) enters the encampment ((e)n2) as a vicious dust storm (尘) is blowing. He breathes so much dirt (土) that he thinks the dirt got even into his heart (小).