SHIP'S LIGHTS AND REGULATIONS 193
Stern Light.
ART. 10.—A vessel which is being overtaken by another shall
show from her stern to such last-mentioned vessel A WHITE LIGHT or
A FLARE-UP LIGHT.
The white light required to be shown by this Article may be
fixed and carried in a lantern, but in such case the lantern shall be
so constructed, fitted, and screened that it shall throw an unbroken
light over an arc of the horizon of 12 points of the compass, viz.,
for 6 points from right aft on each side of the vessel, so as to be
visible at a distance of at least 1 mile. Such light shall be carried
as nearly as practicable on the same level as the side-lights.
Vessels at Anchor.
ART. 11.—A vessel UNDER 150 FEET in length, when at anchor,
shall carry forward, where it can best be seen, but at a height not
exceeding 20 feet above the hull, A WHITE LIGHT in a lantern so
constructed as to show a clear, uniform and unbroken light visible
all round the horizon at a distance of at least 1 mile.
A vessel of 150 FEET or UPWARDS in length, when at anchor,
shall carry in the forward part of the vessel, at a height of not
less than 20, and not exceeding 40 feet above the hull, one such light,
and AT OR NEAR THE STERN of the vessel, and at such a height that
it shall not be less than 15 feet lower than the forward light, AN-
OTHER SUCH LIGHT.
The length of a vessel shall be deemed to be the length appearing
in her certificate of registry.
A vessel AGROUND in or near a fairway shall carry the above
LIGHT OR LIGHTS and the TWO RED LIGHTS prescribed by Article 4 (a).
Signal to Attract Attention.
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 FLAKE-UP LIGHT or use any detonating
signal that cannot be mistaken for a distress signal.
Special Recognition Signals.
ART. 13.—Nothing in these Rules shall interfere with the opera-
tion 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
H