From medieval times to the early 20th century, women kept essential items such as keys close at hand on their "chatelaines." These precursors to purses hung from belts and featured long chains with hooked ends to clutch accoutrements. But when women started working full-time outside the home, cloth handbags—with straps instead of chains and plenty of room for cosmetics and sunglasses—made chatelaines obsolete.But chatelaines survive among estate jewelry dealers and their customers. Part of their appeal lies in their ornate and symbolic designs, which reveal how women's lives have evolved. Where to find them. High-end estate dealers find their best pieces at estate sales. But over the past 20 years, it's been tougher to find intact ones, says Barry Weber, the owner of Edith Weber Co. in New York. Some collectors are interested only in the attachments, such as watches. "I frequently