Article

Real-World Geography: How people use geography and the geographic perspective in their everyday lives and real-world careers.

Illustration by Mary Crooks

Fourth Arm of Defense
The merchant marine, often called the fourth arm of defense, is a fleet of American cargo ships. According to the U.S. Merchant Marine Academy, There are tankers traveling along the west coast with raw petroleum for our refineries; Great Lakes vessels loaded with iron ore, coal or other minerals for America's industry; huge containerships in Eastern ports, their box-like containers filled with manufactured goods; general cargo ships in the Gulf unloading pallets of coffee and crates of fruit; tugboats pushing and pulling barges carrying the Midwest's grain.

These kinds of vessels, owned by U.S. companies, registered and operated under the American flag, comprise the U.S. merchant marine. This fleet of highly productive ships is a major part of our system of commerce, helping guarantee our access to foreign markets for sale of our manufactured goods.

By Stuart Thornton

Wednesday, April 13, 2011

John is the captain of the Sheila McDevitt, a 179-meter (587-foot) cargo vessel that hauls dry bulk goods, including coal, phosphate, dry cement, grain, corn, rice, and sugar.

Speaking from his home in Burnet, Texas, John is modest about his responsibilities. “Overall management is really what I do for the most part,” John says of his job. “I do some navigation duties entering and leaving port also.”

EARLY WORK

Growing up in Palmetto, Florida, John spent a lot of time in and around the water. “From my earliest age, I was at home in the water,” he says. “I’d run out every morning and jump in the water and swim and boat and fish. I had rowboats and sailboats and canoes and everything else that would float.”

John’s father was a commercial fisherman, and his grandfather used to run freight schooners. John learned a lot about boating while going out on the water with his father. “Sometimes, it was scary,” he says. “I just got respect for the sea early on . . . boats being out in bad weather sometimes.”

After studying naval architecture at the University of Michigan at Ann Arbor, John realized he would rather be out on the water than indoors. John was accepted at the U.S. Merchant Marine Academy in Kings Point, New York, where he graduated in 1984.

MOST EXCITING PART OF YOUR WORK

“I just love the traveling,” John says. “I just like to be able to go to all the different places and see the life there. It’s not always very nice places, but it’s interesting just the same.”

MOST DEMANDING PART OF YOUR WORK

“[Making sure] that everything is ready, that the vessel is ready to discharge cargoes, that the machinery is in good condition.”

HOW DO YOU DEFINE GEOGRAPHY?

“I think of basically sea lanes, and how I get from one place in the world to the next by ship.”

GEO-CONNECTION

John says he always has to consider geographic features, including ocean currents and weather patterns, when he is planning safe routes for the Sheila McDevitt.

Traveling to places like China, East Africa, and even North Korea for his job, John has had to deal with many issues in human geography. “When I get into ports, I’m dealing with a lot of different cultures, different rules, different governments and things like that,” he says.

When John first became a captain, he used sextants and LORAN, a radio navigation system, to pinpoint where he was. “Now with GPS, it’s become very easy as far as open ocean navigation,” he says. “We know where we are all the time.”

SO, YOU WANT TO BE A . . . CREWMEMBER OR SHIP’S CAPTAIN

“If you are deck side or even if you go to the engineering side, the sciences are pretty important.”

GET INVOLVED

If you live by the water, take an introductory sailing or boating course.

John says you can familiarize yourself with navigation without using a lot of tools. “With a GPS receiver and latitude and longitude, you can actually pull out a chart or a map and start plotting positions,” he says, “That’s always good practice, or a good way to know if you have an interest in that or not.”

Vocabulary

Term Part of Speech Definition Encyclopedic Entry

canoe

noun, verb

small, open boat with pointed ends.

captain

Noun

person in command of a ship or other vessel.

cargo

Noun

goods carried by a ship, plane, or other vehicle.

cement

Noun

hard material used as a building material or a binding agent for stronger building materials such as concrete.

chart

Noun

type of map with information useful to ocean or air navigators.

Encyclopedic Entry: chart

coal

Noun

dark, solid fossil fuel mined from the earth.

commercial fishing

Noun

industry responsible for catching and selling fish.

current

Noun

steady, predictable flow of fluid within a larger body of that fluid.

Encyclopedic Entry: current

deck

Noun

top surface or "floor" of a ship.

engineering

Noun

the art and science of building, maintaining, moving, and demolishing structures.

familiarize

Verb

to understand how something works or operates.

freight

Noun

goods transported by air, land, or sea for profit.

Global Positioning System (GPS)

Noun

system of satellites and receiving devices used to determine the location of something on Earth.

government

Noun

system or order of a nation, state, or other political unit.

GPS receiver

Noun

device that gets radio signals from satellites in orbit above Earth in order to calculate a precise location.

grain

Noun

harvested seed of such grasses as wheat, oats, and rice.

Encyclopedic Entry: grain

human geography

Noun

the study of the way human communities and systems interact with their environment.

latitude

Noun

distance north or south of the Equator, measured in degrees.

Encyclopedic Entry: latitude

longitude

Noun

distance east or west of the prime meridian, measured in degrees.

Encyclopedic Entry: longitude

LORAN

Noun

(LOng RAnge Navigator) radio navigation system.

map

Noun

symbolic representation of selected characteristics of a place, usually drawn on a flat surface.

Encyclopedic Entry: map

modest

Adjective

refusing to draw attention to oneself.

naval architecture

Noun

branch of engineering dealing with the design, construction, and operation of marine vehicles.

navigation

Noun

art and science of determining an object's position, course, and distance traveled.

Encyclopedic Entry: navigation

phosphate

Noun

type of salt used as fertilizer. Excess phosphates can choke freshwater ecosystems.

plot

Verb

to form a path based on calculations.

port

Noun

place on a body of water where ships can tie up or dock and load and unload cargo.

Encyclopedic Entry: port

radio navigation

Noun

method of navigation based on the source of radio waves being broadcast to determine a vessel's position.

route

Noun

path or way.

rowboat

Noun

watercraft that is maneuvered by oars.

sailboat

Noun

aquatic vessel that uses wind to maneuver and move.

schooner

Noun

large sailing vessel with at least two equal-sized masts.

sea lane

Noun

navigation route used by ships.

sextant

Noun

tool used by navigators to determine latitude and longitude.

weather

Noun

state of the atmosphere, including temperature, atmospheric pressure, wind, humidity, precipitation, and cloudiness.

Encyclopedic Entry: weather

weather pattern

Noun

repeating or predictable changes in the Earth's atmosphere, such as winds, precipitation, and temperatures.

Credits

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Writer

Stuart Thornton

Editors

Jeannie Evers
Kara West

Producer

Caryl-Sue, National Geographic Society

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