IN GILT letters on the ground glass of the door of room No. 962 were the words: "Robbins & Hartley, Brokers." The clerks had gone. It was past five, and with the solid tramp of a drove of prize Percherons, scrub- women were invading the cloud-capped twenty-story office building. A puff of red-hot air flavoured with lemon peelings, soft-coal smoke and train oil came in through the half-open windows.