<P> The largest group of students during the first seven decades of the school were from Martha's Vineyard, and they brought MVSL with them . There were also 44 students from around Henniker, New Hampshire, and 27 from the Sandy River valley in Maine, each of which had their own village sign language . Other students brought knowledge of their own home signs . Laurent Clerc, the first teacher at ASD, taught using French Sign Language (LSF), which itself had developed in the Parisian school for the deaf established in 1755 . From this situation of language contact, a new language emerged, now known as ASL . </P> <P> More schools for the deaf were founded after ASD, and knowledge of ASL spread to these schools . In addition, the rise of Deaf community organizations bolstered the continued use of ASL . Societies such as the National Association of the Deaf and the National Fraternal Society of the Deaf held national conventions that attracted signers from across the country . This all contributed to ASL's wide use over a large geographical area, atypical of a sign language . </P> <P> Up to the 1950s, the predominant method in deaf education was oralism--acquiring oral language comprehension and production . Linguists did not consider sign language to be true "language", but rather something inferior . Recognition of the legitimacy of ASL was achieved by William Stokoe, a linguist who arrived at Gallaudet University in 1955 when this was still the dominant assumption . Aided by the civil rights movement of the 1960s, Stokoe argued for manualism, the use of sign language in deaf education . Stokoe noted that sign language shares the important features that oral languages have as a means of communication, and even devised a transcription system for ASL . In doing so, Stokoe revolutionized both deaf education and linguistics . In the 1960s, ASL was sometimes referred to as "Ameslan", but this term is now considered obsolete . </P> <P> Counting the number of ASL signers is difficult because ASL users have never been counted by the American census . The ultimate source for current estimates of the number of ASL users in the United States is a report for the National Census of the Deaf Population (NCDP) by Schein and Delk (1974). Based on a 1972 survey of the NCDP, Schein and Delk provided estimates consistent with a signing population between 250,000 and 500,000 . The survey did not distinguish between ASL and other forms of signing; in fact, the name "ASL" was not yet in widespread use . </P>

When did asl gain recognition as a language what took so long
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