Lighthouses: FAQ

Updated February 21, 2017 | Factmonster Staff
Source: The United States Coast Guard

Our first lighthouses were actually given to us by Nature. Sailors sometimes used landmarks such as glowing volcanoes to guide them. In the Ancient World, trading ships were eventually built enabling navigators to sail long distances to buy and sell goods. In the days of wooden ships with sails, the wind and waves could easily push them against the rocks and wreck them. And so, the need for lighthouses as warning signals arose.

One of the Seven Wonders of the Ancient World was a lighthouse—the famous Pharos of Alexandria, Egypt. It is the first one that is recorded in history and was built about 280 BC. Those records tell us that it was the tallest one ever built—450 ft. (comparable to a 45-story skyscraper) and used an open fire at the top as a source of light. This fantastic structure survived for 1500 years until it was completely destroyed by an earthquake in the 14th century.

Today we call people who study (or are interested in) lighthouses pharologists. The name comes from that famous lighthouse.

What is a lighthouse?

It is a tower with a bright light at the top, located at an important or dangerous place regarding navigation (travel over water). The two main purposes of a lighthouse are to serve as a navigational aid and to warn boats of dangerous areas. It is like a traffic sign on the sea.

Do all lighthouses look alike?

Although we often think of a lighthouse as a tall, white conical tower, there are many, many variations of design. Depending on its location, it might be tall (where the land was very flat) or short and squat (where there was a high cliff or rocky coast). It could be square, octagonal (with eight sides), conical (like an ice cream cone upside down), or cylindrical (like a very fat pipe).

When the lighthouses were built, they were constructed with whatever materials were most readily available. They were designed to fit the local geographic and climatic conditions. Some are made of stone; others brick, concrete, wood, steel, cast iron, and even tabby (a mixture of shells, lime, sand and water).

Where are lighthouses located?

The United States has several coastlines used by ships from around the world. In the East it borders the Atlantic Ocean, in the West the Pacific Ocean, and in the South the Gulf of Mexico. But we also have another very important area of coastline where the land meets the sea, the Great Lakes. All of these four areas bordering our country need and have lighthouses, as well as some of our more important navigable inland waterways. For example, the Hudson River, Lake Champlain, Chesapeake Bay and San Francisco Bay are also dotted with lighthouses.

How could one lighthouse be distinguished from another?

Years ago, to help the sailor determine his location, the Lighthouse Board (which was in charge of lighthouses from 1852–1910) issued an order to have each lighthouse painted in different colors and/or designs.

But what about night? You can't see colors or patterns at night, but you can see lights. However, unless there was some way to make each light different you could have the same problem. Early on, they built multiple lights (that is, two or three together.) This was one way to help the sailors at sea determine their location, but it was very expensive.

Mounting a group of lights on a rotating framework made it possible to produce a special pattern of light for each lighthouse. The rotating lights made a lighthouse look like it was flashing its light on and off. The invention of the Fresnel (pronounced “Frey Nel”) lens in 1822 was probably the most important discovery in lighting technology. As well as enabling man to produce an unlimited number of flashing combinations, it also intensified (brightened) the light so it could be seen at greater distances.

The Fresnel lens can be compared to a huge lampshade except that it is made of 100s of pieces of beautiful, specially cut glass. It surrounds the lamp bulb. This lens, due to its special design, brightens the glow from the light. It takes the rays of light, which normally scatter in all directions, and bends (refracts and reflects) them, focusing them into a single beam of light. Fresnel lenses are of two types: fixed, which shows a steady light; and revolving, which produces a flash.

The individual flashing pattern of each light is called its CHARACTERISTIC. For example a light can send out a flash every five seconds, or it might have a fifteen-second period of darkness and a three-second period of brightness. Mariners have to look at a light list or a maritime chart that tells what light flashes that particular pattern. Then they are able to determine their position at sea in relation to the land.

What happens in fog when the light isn't visible?

In situations like this there is another method of notifying the mariner, using sound. It is called a foghorn. The first one was used in 1719 at Boston light and it was, of all things, a cannon. Can you imagine being a lighthouse keeper and having to fire the cannon every hour when there was fog? During a long spell of fog you wouldn't get any sleep. Later they tried various other means of making a noise for warning. Fog bells were used as well as steam whistles and reed trumpets and sirens. The sounds they gave out were generally low-pitched and very mournful—almost like a wail. Each one emitted a specific number of blasts every minute so it could be told apart from all others. Today, an automatic sensor, which detects moisture in the air, turns on the fog signals when needed. There are also soundless fog signals called radio beacons (an electronic device).

These fog signals were not placed everywhere. Although some places experience no fog problems, fog-warning devices are very necessary m New England, on the Pacific Coast, and in Alaska.

When were the first lighthouses built in the U.S.?

In colonial times, before we became an independent nation, men realized the need for lighthouses at the major ports to help guide ships into the harbors, to prevent them from crashing, and thereby losing their precious cargoes. So, the first lighthouses were built by the colonies (which were called states after 1776).

Most lighthouses were named for their location, but several were named after ships that wrecked themselves nearby before a lighthouse was built. For example: Alligator Reefs, Pigeon Point, and Ship John Shoal. Others were named because of events that occurred there: Dead Man's Rock, Cape Disappointment, and Execution Rocks.

What were the duties of the lighthouse keepers?

Before the days of electricity, they had to light the lamp at sunset and extinguish it (put it out) at sunrise. During an 8-hour watch at night they had to climb the stairs in the tower one to three times a night to check on the lamp and wind the weights. Some lighthouses have as many as two hundred steps! The brass in the building had to be shined, and all the windows cleaned. Often it took a whole day to clean and polish the lens alone. It was very important to keep both the lens and the lantern room windows clean so the light would not be lessened in any way.

A daily log had to be kept detailing everything from the weather to the amount of fuel consumed. The Keeper also had to tend to the mechanism used to operate the fog signal. During the year many items had to be painted.

The men and women of the Lighthouse Service were among the most dedicated civil servants, often performing in extreme hardship. Abbie Burgess, while also caring for her family, served 38 years at the Matinicus Rock and White Head Light Stations in Maine. Keepers also saved lives. Ida Lewis rescued 18 people during her 39 years at the Lime Rock Lighthouse. Marcus Hanna, the keeper of the Cape Elizabeth Light, is the only man to have won the Medal of Honor and the Gold Lifesaving Medal. Other keepers died on duty. A 1906 hurricane, for instance, destroyed twenty-three lights along the Gulf Coast and killed the keepers at Horn Island and Sand Island. In 1946 a tsunami destroyed the Scotch Cap (Alaska) light and killed the entire crew.

What is happening to lighthouses at present?

Increased mechanization and improved technology have made keepers unnecessary. Today, all of the lighthouses in our country have been automated, except the one at Boston, which still has keepers, for sentimental reasons only. (Boston Light was the first one built on our shores.)

Many of the lighthouses are no longer needed due to advances in technology and they have been or are being turned over to various government agencies or non-profit local organizations to maintain and administer. It is important to keep them in good condition for future generations to learn about their place in the maritime history of our country. It is also a special experience to be able to climb the stairs just as the keepers did and picture what life was like in times past. They also need protection from vandalism and threats of erosion.

What are some interesting facts about lighthouses?

First Lighthouse: Boston, MA (1716)

Oldest Lighthouse in Service: Sandy Hook, NJ (1764)

Newest Shoreside Lighthouse: Charleston, SC (1962)

Tallest Lighthouse: Cape Hatteras, NC (191 ft.)

Highest Lighthouse (above sea level): Cape Mendocino, CA (515 ft.)

First American-built West Coast Lighthouse: Alcatraz Lighthouse (1854)

First lighthouse to use electricity: Statue of Liberty (1886)

First Great Lakes lighthouses: Buffalo, NY & Erie, PA (1818)

Founding of the US Lighthouse Service—7 August 1789

US Lighthouse Service merged with the Coast Guard—7 July 1939

To find a list of lighthouses in the United States, visit the National Park Service: http://www.cr.nps.gov/maritime/ltsum.htm

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