In front of the blackboard, upon a platform, a young man in shirtsleeves, his cuffs caught up by metal clamps, walked up and down. Screwed to the blackboard itself was a telegraph instrument, and from time to time, as this buzzed and ticked, the young man chalked up cabalistic, and almost illegible figures under columns headed by initials of certain stocks and bonds, or by the words “Pork,” “Oats,” or, larger than all the others, “May Wheat.” The air of the room was stale, close, and heavy with tobacco fumes. The only noises were the low hum of conversations, the unsteady click of the telegraph key, and the tapping of the chalk in the marker’s fingers.