"I never heard of them before, for I do not claim to be much of a sailor, though I have given some attention to sailing a steamer since I have been on board of the Guardian-Mother," replied Louis. "I have learned to steer, and I know something about handling the engine. I never was placed in any responsible position on board a vessel, and that is the way to learn all about it." "Now she shows her red light, and we are doing the same thing to her," said Morris. "Here is a bit more mnemonics: 'Green to green, or red to red-- Perfect safety, go ahead!' That is, you cannot see the red or green alone unless you are abreast of the other vessel on one side or the other." "I can remember the two couplets; but both of them assure you only when you are all right. One would like to know what to do when things are not all right," suggested Louis, who had already repeated to himself both of the safety couplets several times. "Of course you know all the lights a vessel is obliged by law to carry at sea, Louis," continued Morris, as they passed the other steamer, distant about a quarter of a mile. "I know that every steamer is obliged to carry a white light on the foremast, not less than twenty feet above the deck, a green light on the starboard side, and a red one on the port side." "That is enough to know, though very minute directions are given in the international rules for placing these lights. I used to be bothered to remember which was which. But a naval officer told me that red was on the port side because that was the color of port wine; and any fellow must be green who could not tell the color on the other side." "Captain Ringgold told me the first part of your rule--port from the color of port wine," added Louis. "Now we have a case in point!" exclaimed Morris with sudden energy, as he pointed to another light in the distance. "That is a red light, and it is on the starboard side of us. This is the position of the greatest danger, for that steamer is running towards us. Here is more poetry:-- 'If to your starboard red appear, It is your duty to keep clear; To act as judgment says its proper-- To port, or starboard, back, or stop her!' That is just as yonder steamer appears in relation to the Maud--red on our starboard, her helmsman has green on his port, and this verse applies to him, as it would to us in his position:-- 'But, when upon your port is seen A steamer's starboard light of green, There's not so much for you to do, For green to port keeps clear of you.'" "She is still a long distance from the Maud; but what am I to do when we come nearer?" asked Louis. "Red to starboard; we must keep out of her way," replied Morris. "She will do nothing, for she has the right of way. Port the helm a little and we shall go astern of her all right." "Where do you find these international rules?" asked the wheelman, as he obeyed the order.