ART. 27. In obeying and construing these rules due regard shall be had to all dangers of navigation and collision, and to any special circumstances which may render a departure from the above rules necessary in order to avoid immediate danger. Sound signals for passing steamers. ART. 28. The words "short blast" used in this article shall mean a blast of about one second's duration. When vessels are in sight of one another, a steam vessel under way, in taking any course authorized or required by these rules, shall indicate that course by the following signals on her whistle or siren, namely: One short blast to mean, "I am directing my course to starboard." Two short blasts to mean, "I am directing my course to port." Three short blasts to mean, "My engines are going at full speed astern." Precaution. ART. 29. Nothing in these rules shall exonerate any vessel, or the owner or master or crew thereof, from the consequences of any neglect to carry lights or signals, or of any neglect to keep a proper lookout, or of the neglect of any precaution which may be required by the ordinary practice of seamen, or by the special circumstances of the case. ART. 30. Nothing in these rules shall interfere with the operation of a special rule, duly made by local authority, relative to the navigation of any harbor, river, or inland waters. Distress signals. ART. 31. When a vessel is in distress and requires assistance from other vessels or from the shore the following shall be the signals to be used or displayed by her, either together or separately, namely: In the daytime— _First._ A gun or other explosive signal fired at intervals of about a minute. _Second._ The international code signal of distress indicated by N C. _Third._ The distance signal, consisting of a square flag, having either above or below it a ball or anything resembling a ball. _Fourth._ A continuous sounding with any fog-signal apparatus. At night— _First._ A gun or other explosive signal fired at intervals of about a minute. _Second._ Flames on the vessel (as from a burning tar barrel, oil barrel, and so forth). _Third._ Rockets or shells throwing stars of any color or description, fired one at a time, at short intervals. _Fourth._ A continuous sounding with any fog-signal apparatus. INLAND RULES: I. ENACTING CLAUSE, SCOPE, AND PENALTY Whereas the provisions of chapter eight hundred and two of the laws of eighteen hundred and ninety, and the amendments thereto, adopting regulations for preventing collisions at sea [i.e., international rules of left-hand column], apply to all waters of the United States connected with the high seas navigable by seagoing vessels, except so far as the navigation of any harbor, river, or inland waters is regulated by special rules duly made by local authority; and