Naviguessing – a thing of the past

Mark Nelson

Mark Nelson, 
Contributor

When a ship travels the seven seas, it racks up sea miles, a distance measured in nautical miles. A nautical mile is exactly 6,076 feet. For simplicity’s sake, sailors say it is 6,000 feet or 2,000 yards.

An important nautical measurement is a cable, which is one-tenth of a nautical mile, or 200 yards. In the Stan Rogers classic sea shanty Barrett’s Privateers, an unofficial anthem for many Canadian sailors, the Antelope chased an American ship until ‘at length they stood two cables away’. Unfortunately, 400 yards seemed to be the operational range of an American cannon, resulting in disaster for the Antelope.

The person who knows the distance the ship has travelled is the Navigating Officer, abbreviated Nav O, and informally known as the navigator. It wasn’t long ago that we kindly referred to this person as the navi-guesser since the ship’s position was based on a series of best guesses, comprised of dead reckoning. Dead reckoning is a method of determining a vessel’s current position by combining the last known position with the vessel’s speed, elapsed time, and course steered. Originally, dead was spelled ‘ded,’ for ‘deduced.’ Dead reckoning a ship’s position is now a thing of the past, as every HMC ship is fitted with GPS-enabled computer-based navigation systems and electronic charts.

Other navigational fixes encompassed cocked hats, a flawed navigational fix comprised of three bearing lines that do not meet, and the occasional basket of eggs, an astronomical fix consisting of a collection of circles, occurring when the sun is directly overhead.

As harbour bottoms may shift with the currents over time, sailors must know the depth of the water below the hull. It is measured with an echo sounder that broadcasts a sound wave and measures the current in meters, feet or fathoms, a fathom being six feet. Before echo sounders, however, a member of the ship’s crew would lower a hand lead line, a slender line with a lead weight, to measure the depth of the water below the ship.

When the lead weight struck the bottom, markings on the line would indicate the depth of the water. After reporting the depth to the bridge, they would raise the line and perform the measurement again in a few minutes or as soon as required by the command. Sometimes, the sailor would not raise the line completely and let it drift in the water before making the next measurement. This was known as swinging the lead and considered the lazy way to perform this duty.

Today, a lazy sailor is sometimes said to be swinging the lead, or more directly, might be referred to as skiving, or avoiding work. For some sailors, skiving is considered an art, and they pride themselves on their ability to skive.

The author of Jackspeak of the Royal Canadian Navy and Whiskey 601, Mark Nelson developed a love of the Navy’s language and lifestyle over his 26-year career in the service. After retiring as a Chief Petty Officer Second Class, he now works as a library systems specialist at Red River College Polytechnic in Winnipeg, Man.

Follow Mark on Twitter @4marknelson

 

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