Who founded the first free school for hearing impaired?

The first free school for the hearing impaired is generally attributed to Thomas Braidwood. While he wasn't entirely altruistic (he charged for his services initially and kept his teaching methods secret), his school in Edinburgh, Scotland, in the 18th century is considered a landmark in the education of the deaf. Later schools built upon his work and became more openly accessible and free, but his school was the foundational development.