Language resources are typically defined and created for application in speech technology contexts, but the documentation of languages which are unlikely ever to be provided with enabling technologies nevertheless plays an important role in defining the heritage of a speech community and in the provision of basic insights into the language oriented components of human cognition. This is particularly true of endangered languages. The present case study concerns the documentation both of the birth and of the endangerment within a rather short space of time of a `spirit language', Medefaidrin, created and used as a vehicular language by a religious community in South-Eastern Nigeria. The documentation shows phonological, orthographic, morphological, syntactic and textual typological features of Medefaidrin which indicate that typological properties of English were a model for the creation of the language, rather than typological properties of the enclaving language, Ibibio. The docu...