When you sail for London you have to set your watch ahead each night when you go to bed, so that when you reach London your watch will be five hours ahead of the time you started with. You will then be just right with London time when you reach London. When you sail back you must put your watch back too. If you telephoned to London now at 10 o’clock in the morning and asked them what time it was they would say 3 P. M.

The clocks on board ship look the same as our clocks at home, but they strike differently. Our clocks, as you know, strike once for 1 o’clock, twice for 2 o’clock, and so on, but on board ship a clock strikes two bells for each hour from 1 o’clock to 4 o’clock, when it strikes eight times. It strikes one bell more for the in-between halves of the hour. Then it starts all over again—one stroke at 4:30, two at 5, and so on—never more than eight strokes altogether.

“A watch” on board ship doesn’t mean only a watch that you put in your pocket. It means something else too. A ship doesn’t stop going at night. A ship must keep on going, night as well as day, so the men, the officers and crew who run the ship, take turns at running the ship, as they can’t stay awake all the time, and their turns are called “watches,” because they must be wide awake and watching when it is their “watch.” Some men are running the engines, some are steering the ship, and some are just watching out to see that they do not run into other ships while the others are sleeping.

How can the captain, when he leaves New York, know the way to go to London, when all the ocean in front of him as far as he can see on every side is just broad flat water or rolling waves or thick fog, with no sign-posts to guide him?

Right in front of the steering-wheel is a box in which is a little pointer that, no matter how much the ship rises and falls, or twists and turns, or rears and plunges, always points one way. The box with its pointer is called a compass. You know what a magnet is—a little thing like a small horseshoe that pulls needles and nails to it. Well, near the North Pole there is a spot on the World like a magnet and this spot pulls all the compasses on the World toward it. So that spot on the World that pulls all the compasses toward it is called the Magnet-ic pole, though there is no pole. This Magnetic pole is where the stem would be if the World were an orange or an apple, though there is no stem.