Chang and Eng were born in 1811 in Siam's Mekong Valley conjoined near the breastbone, facing one another, though in time they taught their flesh to stretch enough so that they could both face outward. Freaks in the truest sense—Siamese twins (the term began with them) are rare; an embryo has to begin to split within weeks of conception and then, for whatever reason, stop, creating a partially separated egg, which then continues to mature—the twins left Siam at 17, toured in circuses in Europe and the United States (including, famously, P. T. Barnum's), and then, in 1839, hung up their specially made conjoined tuxedo and retired to the American South. They married a pair of not-conjoined sisters, and fathered, in each other's presence, 21 children, two of whom were deaf-mutes. In tribute to Chang and Eng, Seattle artist Jessica Grilihas sliced up two tiny plastic deer and mounted their heads together on a varnished wood base. She took the liberty to make their union craniopagus, a kind of facial fusion, which is very uncomfortable and extremely rare, though not unheard of. CHRISTOPHER FRIZZELLE