SOUND SIGNALS on the THAMES

⑀                I am altering my course to STARBOARD

⑀⑀              I am altering my course to PORT

⑀⑀⑀            I am operating ASTERN propulsion

⑀⑀⑀⑀ ⑀    I am turning fully round to STARBOARD

⑀⑀⑀⑀ ⑀⑀   I am turning fully round to PORT

⑀⑀⑀⑀⑀        I do not understand your intentions; keep clear

               (I doubt whether you are taking sufficient action to avoid a collision)

■■■    I am about to get underway / enter the fairway

              or: I am approaching a blind bend

■■■ ⑀⑀      I am unable to manoeuvre (not under command)

■■■ ■■■ ⑀   I intend to overtake you on your STARBOARD side

■■■ ■■■ ⑀ ⑀    I intend to overtake you on your PORT side

■■■ ⑀ ■■■ ⑀       I agree to be overtaken