ORGANIC LAWS GOVERNING U.S. COAST GUARD 41 



(b) A vessel of 150 feet or more in length, when at anchor, shall 

 carry near the stem of the vessel, at a height of not less than 20 feet 

 above the hull, one such light, and at or near the stern of the vessel and 

 at such a height that it shall be not less than 15 feet lower than the 

 forward light, another such light. Both these lights shall be visible 

 at a distance of at least 3 miles and so placed as to be as far as possible 

 visible all round the horizon. 



(c) Between sunrise and sunset every vessel when at anchor shall 

 carry in the forepart of the vessel, where it can best be seen, one black 

 ball not less than 2 feet in diameter. 



(d) A vessel engaged in laying or in picking up a submarine cable 

 or navigation mark, or a vessel engaged in surveying or underwater 

 operations, when at anchor, shall carry the lights or shapes prescribed 

 in Rule 4(c) in addition to those prescribed in the appropriate preced- 

 ing sections of this Rule. 



(e) A vessel aground shall carry the light or lights prescribed in 

 sections (a) or (b) and the two red lights prescribed in Rule 4(a). 

 By day she shall cany, where they can best be seen, three black balls, 

 each not less than 2 feet in diameter, placed in a vertical line one 

 over the other, not less than 6 feet apart. 



(f) A seaplane on the water under 150 feet in length, when at 

 iinchor, shall carry, where it can best be seen, a white light, visible all 

 round the horizon at a distance of at least 2 miles. 



(g) A seaplane on the water 150 feet or upwards in length, when at 

 anchor, shall carry, where they can best be seen, a white light forward 

 and a white light aft, both lights visible all round the horizon at a 

 distance of at least 3 miles; and, in addition, if the seaplane is more 

 Ihan 150 feet in span, a white light on each side to indicate the maxi- 

 mum span, and visible, so far as practicable, all round the horizon at a 

 distance of 1 mile. 



(h) A seaplane aground sliall carry an anchor light or lights as 

 prescribed in sections (f) and (g), and in addition may carry tAvo 

 red lights in a vertical line, at least 3 feet apart, so placed as to be 

 visible all round the horizon. 



33 U.S.C. 1072 (Rule 12) 



Every vessel or seaplane on the water 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 a detonating or other 

 efficient sound signal that cannot be mistaken for any signal authorised 

 elsewhere under these Rules. 



33 U.S.C. 1073 (Rule 13) 



(a) 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 ships of war, for vessels 

 sailing under convoy, for Hshing vessels engaged in fishing as a fleet 

 or for seaplanes on the water. 



(b) Whenever the Government concerned shall ha've determined 

 that a naval or other military vessel or waterborne seaplane of special 

 construction or purpose cannot comply fully with the provisions of 

 any of these Rules with respect to the number, position, range or arc 



