1840 First lighthouse tender, or supply vessel, of the US Lighthouse Service goes into service.
1877 Kerosene introduced as a fuel in US lighthouses; illuminants such as sperm oil, rapeseed oil, and lard oil have been used.
1884 First uniforms introduced for male lighthouse keepers, as well as masters, mates, and engineers of lightships and tenders. (Female keepers not required to wear a uniform.)
1915 US Coast Guard established by merging US Life-Saving Service and US Revenue Cutter Service.
1917 First telephones installed at all Coast Guard stations and the most important lighthouses.
1918 First US lightship sunk by an enemy, the Diamond Shoals Lightship off the Outer Banks in North Carolina; all crew embers survive.
1936 US Lighthouse Service declared in an official report to be the ''most decentralized branch of government," with 99 percent of its approximately 5,000 employees working somewhere other than in Washington.
1939 Lighthouse Service abolished and merged into Coast Guard; lighthouse keepers may stay on as civilian keepers or join the Guard.
1990 All US lighthouses are automated by this year, with the exception of Boston Light, which is still staffed.
1999 Cape Hatteras Lighthouse, the country's tallest at 200 feet, moved from the eroding Outer Banks shoreline, becoming the tallest structure ever moved.
2000 National Historic Lighthouse Preservation Act becomes law, letting nonprofit groups compete with government agencies for ownership of lighthouses declared excess property by the Coast Guard.
2003 Coast Guard is transferred from the Department of Transportation to the newly created Department of Homeland Security.
SOURCE: American Lighthouse Foundation, Wells, Maine.