Living your life by a compass
This, from the Skipper... OneLIVING YOUR LIFE BY A COMPASS “Live your life by a compass not a clock” is a quote from Stephen R. Covey’s book “First Things First”. The phrase is a metaphor that is often used to convey the idea that if you have a sense of direction and purpose, the passage of time is not that important. A compass is used by sailors to navigate, to find their way, and to stay on course. A clock, on the other hand, is used to measure time, to keep track of the hours and minutes, and to plan their voyage. In the same way, living your life by a compass means having a clear sense of direction and purpose, and living your life by a clock means being aware of the passage of time and using it effectively. It is a reminder to stay focused on the goal and apply your time management skills. It may be good advice in a metaphorical sense, but in a literal sense, for marine navigation, both the compass and the clock are indispensable tools, and in a seafaring life, their importance cannot be understated. The compass has been used for centuries by sailors to find their way on the high seas. Exploration of the ancient world would not have been possible without it. No matter the size of the ship, or the length of the voyage, once at sea and making way, the ship needs a magnetic compass, a navigator, and a helmsman. Although on smaller vessels the helmsman and navigator may be one in the same person. If one’s goal is to safely reach a desired destination at sea, accurate navigation is essential. It’s the navigator’s job to plot a safe course and to provide the helmsman with a heading to steer at any point in time, as determined by the helmsman’s reading of the compass. However, the actual heading, or the direction the boat is pointing at any given moment, can change frequently and unpredictably. So the helmsman must constantly make small steering adjustments to maintain the desired heading. Given a know starting point (a fix), a well maintained heading, and a constant speed (S), the ship will move through the water a certain distance (D) over a given time period (T). How the ship’s speed is determined is another topic all together, but suffice to say there have been many methods used over the centuries. The instruments used today to measure the ship's speed are ubiquitous. The navigator knows that the ship’s course, or the direction the boat actually moves through the water (as plotted on a chart), will be affected by the prevailing currents and winds, so it may deviate from the course determined from the ship’s speed and heading at any given point in time. So, when determining a heading for any desired course, the navigator must take into account the prevailing conditions. The significance of the clock, as an aid for navigation, became much more important in the 18th century when accurate knowledge of the time over a long sea voyage was vital for effective navigation, lacking electronic or communications aids. The first true chronometer was the life work of one man, John Harrison, spanning 31 years of persistent experimentation and testing that revolutionized naval (and later aerial) navigation1. A marine chronometer is a precision timepiece that is carried on a ship and employed in the determination of the ship’s position by celestial navigation. It is used to determine longitude by comparing Greenwich Mean Time (GMT), and the time at the current location found from observations of celestial bodies1. The celestial observations required to accurately determine a ship's latitude were made possible with the invention of Hadley's Quadrant in 1730. The Quadrant could measure angles up to 90° in an arc of only 45° and so was known by two names—Hadley’s quadrant or an octant2. A major use of Hadley’s quadrant was to measure the angular elevation of the North Star or the Sun above the horizon in order to find one’s latitude2. And with the invention of the marine chronometer, these observations would prove to be the means by which longitude could be determined.
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