>> this side depicts the eight horses of wang mu.mu was the fifth emperor of the zhou dynasty, who boarded a chariot in search of the peaches of immortality in heaven. >> according to the myth, each of his magical chargers had a special talent. one galloped without touching the ground, while another ran as fast as the sun's shadow. now, wang mu ruled about 1,000 years before christ. lark knows the screen is not that old. but the myth becomes a popular subject for chinese poets and artists and a symbol for the later emperors. but which one? lark hopes the inscription on the other side holds the answer. his crack research staff soon has a translation of the ancient chinese. what does it say? >> well, the inscription's really interesting, because it specifically mentions qianlong. >> emperor qianlong reigned during most of the 18th century, which is why lark is so excited by his next discovery. >> there's a date mentioned -- "30 years earlier, in 1743, when i commissioned a painting about horses." so that takes us up to 1773 or so. >> s