The license of any person, firm or corporation violating any of the terms of this chapter or any of the rules and regulations established and adopted by the Director of Public Safety shall be revoked by the Director. The Director is hereby authorized and empowered to deny, for reasonable cause, applications for licenses. The Director shall notify such applicant or licensee of any hearing of the Director involving the denial or revocation of such license. Such notification shall be by registered mail directed to the last address of the licensee on file with the Director.