The pictographs themselves were likely inspired by The Kentuckies in New-York (1834) by William Alexander Caruthers, where similar writing is the work of a black slave.
Same piktogramy w książce były prawdopodobnie inspirowane pracą The Kentuckies in New-York (1834) Williama Alexandra Carruthera, gdzie podobne pismo jest tworem czarnoskórego niewolnika.