"Easy," answered the fun-loving student. "I mixed up a sticky preparation of glue, varnish, gum and so on, made it into a powder, and put it in alcohol. Then I sneaked in past the doorkeeper I had bribed, and sprinkled the stuff all over the floor. There was no color to it, and they didn't notice it. The alcohol kept it from sticking until after the march, and then, when the alcohol evaporated, it left the gum ready to do its work."