Using A Watch and The Sun As A Compass
An analog watch can be used to locate north and south. The Sun appears to move in the sky over a 24 hour period while the hour hand of a 12-hour clock face takes twelve hours to complete one rotation. In the northern hemisphere, if the watch is rotated so that the hour hand points toward the Sun, the point halfway between the hour hand and 12 o'clock will indicate south. For this method to work in the southern hemisphere, the 12 is pointed toward the Sun and the point halfway between the hour hand and 12 o'clock will indicate north. During daylight saving time, the same method can be employed using 1 o'clock instead of 12.
The method depends on the assumption that the azimuth of the Sun changes at a constant rate during a day. Strictly, this is true only when the observer is at one of the Earth's poles. Seen from moderately high latitudes, say more than 50 degrees North or South, the Sun's azimuth changes at a rate that is sufficiently constant to allow this method to be useful. Seen from lower latitudes, the Sun's azimuth changes much more rapidly around noon than at other times of day. In an extreme case, when the Sun passes directly overhead at noon, its azimuth abruptly changes by 180 degrees, from due East to due West. Obviously, this completely invalidates the use of a watch as a compass. There are also relatively minor inaccuracies due to the difference between local time and zone time, and due to the equation of time.
Famous quotes containing the words watch, sun and/or compass:
“I don’t like comparisons with football. Baseball is an entirely different game. You can watch a tight, well-played football game, but it isn’t exciting if half the stadium is empty. The violence on the field must bounce off a lot of people. But you can go to a ball park on a quiet Tuesday afternoon with only a few thousand people in the place and thoroughly enjoy a one-sided game. Baseball has an aesthetic, intellectual appeal found in no other team sport.”
—Bowie Kuhn (b. 1926)
“These modern ingenious sciences and arts do not affect me as those more venerable arts of hunting and fishing, and even of husbandry in its primitive and simple form; as ancient and honorable trades as the sun and moon and winds pursue, coeval with the faculties of man, and invented when these were invented. We do not know their John Gutenberg, or Richard Arkwright, though the poets would fain make them to have been gradually learned and taught.”
—Henry David Thoreau (1817–1862)
“It is the star to every wand’ring bark,
Whose worth’s unknown, although his height be taken.
Love’s not Time’s fool, though rosy lips and cheeks
Within his bending sickle’s compass come;
Love alters not with his brief hours and weeks,
But bears it out even to the edge of doom.”
—William Shakespeare (1564–1616)