On January 2, oil prices hit a milestone when a trader on the New York Mercantile Exchange bid $100 a barrel for crude oil futures. Since then, oil has risen and fallen and risen again. The effect of such turbulence on public confidence (as well as on prices at the pump) has prompted increased interest in oil trading. And, perhaps because they are more photogenic than numbers on a screen, the oil traders themselves, whose bizarre gesticulations (known as "open outcry" trading) have become a metonym for the market. Some suggest that open outcry - trading via shouts and hand signals - is a dying art, threatened by electronic systems. Yet Raymond Carbone, who trades energy options on the New York exchange, is sanguine: "People have been saying that these signals will only be around for another couple of years. But they've been saying that for a decade." And, he notes, "I can signal a trade faster than you can type it." Here, Mr.Carbone demonstrates the hand signals he uses to make himself understood in turbulent times. Published 7 April, 2008, The New York Times Click here for an interactive guide.