00:00 This podcast episode is about how lighthouses work.

04:45 Lighthouses serve as highly visible signals to ships, using fire or light to indicate treacherous waters, and also differentiate one lighthouse from another during the day.

09:20 Lighthouses have a long history, dating back to ancient times, and have evolved from bonfires on cliffs to using lanterns and eventually the invention of the Fresnel lens, which greatly improved their effectiveness and range.

14:32 Lighthouses were initially made of wood and had the potential to burn down or be destroyed by rough weather, but over time they became sturdier with the use of materials like steel and concrete.

20:11 Lighthouses in modern times are built with concrete and steel, and lighthouse keepers in the late 19th century earned about $200 annually, which is equivalent to $5,000 today, and were provided with provisions, making it an ideal job for those who enjoyed solitude and saving money.

25:32 By the 1960s, the Coast Guard had automated and modernized most lighthouses, leaving only 60 out of 1,000 with people still working there, and today there is only one lighthouse in the United States that is still operational and has a person living there as a tour guide.

30:25 Lighthouse keeping was often a family business, with many lightkeepers coming from a long line of seafaring types and feeling a close connection to the sea.

35:25 Lightkeepers were not only responsible for providing light and signals, but were also known to go out and rescue people in dangerous situations, such as Ida Lewis who rescued 18 confirmed people and possibly more throughout her career as a lightkeeper.

40:20 The Pharaohs of Alexandria is the oldest known lighthouse and was possibly the tallest structure in the world at 450 feet, and it was found underwater in 1994.

45:06 Lighthouses in the US are estimated to number around 680, with Michigan having the most at 120, and worldwide there are estimated to be over 17,000 lighthouses in 250 countries, with the brightest one being Oak Island in North Carolina.

50:05 Control Burns, also known as prescribed burns, are coordinated and overseen by licensed burn bosses who create burn plans, light the fires, and work with local fire departments and volunteers to manage the burns, and in addition to their benefits for habitat and wildlife management, Control Burns can also promote early germination of desired plant species due to the charred earth absorbing more light and heating the soil more quickly.