Visible speech is the name of the system used by Alexander Melville Bell , who was known internationally as a teacher of speech and proper elocution and an author of books on the subject. The system is composed of symbols that show the position and movement of the throat, tongue, and lips as they produced the sounds of language and it is a type of phonetic alphabet. The system was used to aid the deaf in learning to speak. Alexander Graham Bell learned the symbols, assisted his father in giving public demonstrations of the system and mastered it to the point that he later improved upon his father's work. Eventually Alexander Graham Bell became a powerful advocate of visible speech and oralism in the United States. He was helped to pursue his mission by the money he earned from his patent of the telephone.