Martha's Vineyard, an island five miles off the southeastern shore of Massachusetts in the U.S., is notable for its history of the majority of sign language users.
The population on the Martha's Vineyard island in the 18th century had a high rate of deaf heredity. By the mid-1700s, inhabitants, both deaf and hearing islanders, developed an indigenous signed language, called Martha's Vineyard Sign Language (MVSL). The birth rate for deaf children ws 1 in 155 on the island.
Groce, Nora Ellen. Everyone here spoke sign language: Hereditary deafness on Martha's Vineyard. Harvard University Press. 1985.
Kageleiry, J. (1999). "The island that spoke by hand." Yankee 63(3), p48.
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