The information contained in this section is taken verbatim from HISTORICALLY FAMOUS LIGHTHOUSES - CG-232. Although the format has been changed slightly for better reading and display. BJ 'n Cindy

Under the supervision of the United States Coast Guard, there is only one manned lighthouses in the entire nation. There are hundreds of other lights of varied description that are operated automatically. And, as technology improves, more and more lighthouses are being operated without a full time crew. Indeed, many of the isolated lighthouses described in this booklet are scheduled for automation.

In the course of our history as a nation, and before that as British colonies, we have built hundreds of lighthouses, some of which still stand though now inactive, having been sold for private residential or other use. Many have been rebuilt and not a few have succumbed to the ravages of time. The history of our lighthouses thus parallels the history of our nation.

Since 1716, when the Province of Massachusetts built Boston Light, scarcely a year has passed that has not seen a new light structure erected somewhere along our sea coasts, on our navigable rivers, or along our lake shores. To tell the story of these lighthouses would be a major undertaking. These stories of some of them, however, have been selected chiefly for their historical interest. Others have been included because their unique locations or types of construction are of more than usual interest.

The lighthouse typifies maritime safety. As part of our early coastal defense system, they played a major role in important Coast Guard duties related to military readiness. Additionally, the light’s strategic locations along our coasts aided another early Coast Guard function, law enforcement, by making it possible for cutters to judge their distances from the coast and so prevent smuggling operations within the three-mile limit.

The stories of 56 lighthouses have been told here. The stories of hundreds of others, of equal interest, could have been included had space permitted.

The oldest lighthouse described is the Boston Light built in 1716. The newest in this booklet is Buzzards Bay Light which is located some five miles off the Massachusetts coast, replacing a lightship that had been there for many years.

The distance these lights are visible has been given in the geographical range. The theoretical visibility of a light in clear weather depends upon two factors, the height of the light above water, and its intensity. The height controls what is known as the geographic range, while the intensity controls what is known as the luminous range. As a rule, for the principal lights the luminous range is greater than the geographic, and the distance from which such lights are visible is limited by the earth’s curvature only. Under some atmospheric conditions the glare or loom of these lights, and occasionally the light itself, may be visible far beyond the computed geographic range. On the other hand, and unfortunately more frequently, these distances may be lessened by fog, rain, snow, haze, or smoke.

Some of the terms in this booklet may be new to readers. A short glossary of terms follows:

Candlepower-The luminous intensity of a light expressed in candles.
Lantern-The glassed-in enclosure on the top of an attended lighthouse which surrounds and protects the lens. Sometimes the entire piece of illuminating apparatus is referred to as the lantern.
Prism-A device for refracting light.
Radiobeacon-Electronic apparatus which transmits a radio signal for use in locating a mariner’s position.
Reflector-An optic which by reflection changes the direction of a beam of light.
Classification of lenses-Lenses are classified as to size by "order", the first order being the largest and the sixth order the smallest. The actual size of a lens is expressed by its inside diameter. The following is a list of the standard lenses:
SizeInside diameter (inches)MMApprox. Height
1st72 7/16"18407' 10"
2nd 55 1/8"14006' 1"
3rd 39 3/8"10004' 8"
3 1/229 1/2"7503' 8"
4th 19 11/16"5002' 4"
5th 14 3/4"3751' 8"
6th 11 3/4"3001' 5"

The numbers in parentheses in the text refer to source of information as indicated in the bibliography on page 88.

Lighthouses are arranged alphabetically by states and by the name of the light within the state.

The United States Coast Guard is a unique service. It is one of the five branches of the armed forces of the U. S. During time of peace it operates under the Department of Transportation. During time of war, or at the direction of the President, it operates under the Secretary of the Navy. The Coast Guard is responsible for a number of missions, including search and rescue, oceanographic research, maintenance of aids to navigation, icebreaking, merchant marine safety, port safety, law enforcement and military readiness.