Special signals.
Art. 12. Every vessel may, if necessary in order to attract attention, in addition to the lights which she is by these rules required to carry, show a flare-up light or use any detonating signal that can not be mistaken for a distress signal.
Naval lights and recognition signals.
Art. 13. Nothing in these rules shall interfere with the operation of any special rules made by the Government of any nation with respect to additional station and signal lights for two or more ships of war or for vessels sailing under convoy, or with the exhibition of recognition signals adopted by shipowners, which have been authorized by their respective Governments and duly registered and published.
Steam vessel under sail by day.
Art. 14. A steam vessel proceeding under sail only, but having her funnel up, shall carry in daytime, forward, where it can best be seen, one black ball or shape two feet in diameter.
INTERNATIONAL RULES: III. SOUND SIGNALS FOR FOG, AND SO FORTH
Preliminary.
Art. 15. All signals prescribed by this article for vessels under way shall be given:
First. By "steam vessels" on the whistle or siren.