DinomaniaAt once reptilian and avian, dinosaurs enable us to imagine a world far beyond the usual boundaries of time, culture, and physiology. We have envisioned them in diverse and contradictory ways, reflecting, in part, our changing conceptions of ourselves. Their discovery, around the start of the nineteenth century, was intimately tied to our awareness of geological time; their vast size and power called to mind railroads, battleships, and factories,