  In their discussion of the development of ISN, however, Kegl, Senghas and Coppola (1999) show that things are not quite this  straightforward. ISN did not develop ‘in one leap,’ from  the very rudimentary homesigns or ‘Mimicas’ spoken by  individual deaf students. Instead, its evolution was more gradual and was preceded by the creation of what Kegl et al. call “Lenguage de Signos Nicaragüense” (LSN), a kind of “pidgin or  jargon” (181) that “developed from the point when these  homesigners came together in the schools and began to share their  homesigns with each other, quickly leading to more and more shared  signs and grammatical devices” (180). In addition, the signers  had access to Spanish language dictionaries, and their language was  also influenced by the signing of Spanish-speaking, non-deaf teachers at the schools — signing which likely incorporated such  grammatical devices of the teachers' language as were transferable to a non-vocal medium. (K. Stromswold, private communication.)