one blast, when on the
port tack two blasts in succession, and when with the wind abaft the
beam three blasts in succession.

(_d_) A vessel when at anchor shall at intervals of not more than
one minute ring the bell rapidly for about five seconds.

(_e_) A vessel at anchor at sea, when not in ordinary anchorage
ground and when in such a position as to be an obstruction to vessels
under way, shall sound, if a steam vessel, at intervals of not more than
two minutes, two prolonged blasts with her whistle or siren, followed by
ringing her bell; or, if a sailing vessel, at intervals of not more than
one minute two blasts with her fog horn, followed by ringing her bell.

(_f_) A vessel when towing shall, instead of the signals prescribed
in subdivisions (_a_) and (_c_) of this article, at intervals
of not more than two minutes sound three blasts in succession, namely,
one prolonged blast followed by two short blasts. A vessel towed may
give this signal, and she shall not give any other.

(_g_) A steam vessel wishing to indicate to another "The way is off
my vessel; you may feel your way past me" may sound three blasts in
succession, namely, short, long, short, with intervals of about one
second between them.

(_h_) A vessel employed in laying or picking up a telegraph cable
shall on hearing the fog signal of an approaching vessel sound in answer
three prolonged blasts in succession.

(_i_) A vessel under way which is unable to get out of the way of
an approaching vessel through being not under command or unable to
maneuver as required by these rules shall on hearing the fog signal of
an approaching vessel sound in answer four short blasts in succession.

Sailing vessels and boats of less than 20 tons gross tonnage shall not
be obliged to give the above-mentioned signals, but if they do not they
shall make some other efficient sound signal at intervals of not more
than one minute.

SPEED OF SHIPS TO BE MODERATE IN FOG, ETC.

ART. 16. Every vessel shall in a fog, mist, falling snow, or heavy rain
storm go at a moderate speed, having careful regard to the existing
circumstances and conditions.

A steam vessel hearing, apparently forward of her beam, the fog signal
of a vessel the position of which is not ascertained shall, so far as
the circumstances of the case admit, stop her engines, and then navigate
with caution until danger of collisi