诚信

诚 = 成 + 讠 : Charlie Chaplin (ch) wants to visit engine, but he's held up at the entrance ((e)ng2). If he wants to enter he has to pass a lie detector test first. He readily takes the test and answers all questions very honestly (诚), and the progress bar mounted on top of an advertising column (讠) shows steady progress. At the very end however the progress bar is stuck at 99% (成) and won't progress regardless of how honest (诚) Charlie answers his questions.

信 = 亻 + 言 : Marie Curie and Rosa Luxemburg are reading a letter of Karl Marx to the public in the encampment's bathroom. To make the message really come across to the people they use a megaphone.