Curious About Lighthouses

PODCAST 227: CURIOUS ABOUT LIGHTHOUSES

RELEASE DATE: SUNDAY, FEBRUARY 5TH, 2023

D:  HELLO, AND WELCOME BACK TO THE CURIOUS KID PODCAST.  FOR MANY CENTURIES, SAILORS HAVE RELIED ON LIGHTHOUSES TO KEEP THEM SAFE AT SEA.  WHY DO LIGHTHOUSES EXIST, WHAT DO THEY DO, AND HOW DO THEY WORK?  LET’S LEARN ALL ABOUT IT.

O:  DOUBLE-MAILBAG!

D:  DOUBLE-MAILBAG!

“MY NAME IS MAXWELL.  I LIVE IN WASHINGTON STATE.  I’M 5 YEARS OLD AND I’M CURIOUS ABOUT LIGHTHOUSES.  WHEN AND WHERE WAS THE FIRST LIGHTHOUSE BUILT?  HOW DID THEY GET THEIR NAME AND WHAT IS THEIR PURPOSE?  I LOVE YOUR SHOW SO MUCH.  I LISTEN EVERY MORNING ON MY WAY TO SCHOOL WITH MY MOMMY AND MY BABY BROTHER CYRUS.  CAN’T WAIT TO HEAR ALL ABOUT LIGHTHOUSES.

MAXWELL AND CYRUS FROM WASHINGTON STATE”

“HI JACOB AND OLIVIA, MY NAME IS KAI, AND I’M 6 YEARS OLD.  I LIVE IN ADELAIDE, AUSTRALIA.  I LIKE TRAINS, PLANES, AND SHIPS, AND I’M LUCKY BECAUSE WE HAVE SPECIAL MUSEUMS FOR EACH OF THESE THINGS IN ADELAIDE (ALL ON THE SAME STREET).  I LISTEN TO YOUR SHOW IN THE CAR ON SPOTIFY, WHEN I’M GOING TO SCHOOL.  I HAVE LISTENED TO ALMOST ALL YOUR EPISODES.  I LIKE THE INTERESTING TOPICS YOU HAVE, AND THE QUESTION OF THE WEEK.  I’M INTERESTED TO LEARN ABOUT LIGHTHOUSES.  WHEN WAS THE FIRST LIGHTHOUSE BUILT, AND HOW TALL IS THE TALLEST LIGHTHOUSE?  THANKS FOR MAKING SUCH A FANTASTIC SHOW.

KAI FROM ADELAIDE, AUSTRALIA”

O:  WE ARE SO EXCITED TO LEARN ABOUT LIGHTHOUSES.  MAXWELL, CYRUS, AND KAI HAVE BEEN WAITING SINCE 2021 FOR US TO GET CURIOUS ABOUT LIGHTHOUSES FOR THEM.  THANK YOU SO MUCH FOR YOUR PATIENCE.  LET’S LEARN ABOUT LIGHTHOUSES FOR MAXWELL, CYRUS, AND KAI.

D:  LET’S ALSO USE ONE OF KAI’S QUESTIONS FOR OUR QUESTION OF THE WEEK.

O:  THE QUESTION OF THE WEEK IS, HOW TALL IS THE TALLEST LIGHTHOUSE IN THE WORLD?

D:  WHILE YOU’RE THINKING ABOUT THE ANSWER, LET’S LEARN ALL ABOUT LIGHTHOUSES, STARTING WITH WHY WE NEEDED THEM IN THE FIRST PLACE.  

O:  LIGHTHOUSES PROVIDE LIGHT TO WATERWAYS, HELPING SAILORS AVOID HAZARDS, LIKE REEFS AND ROCKS.  MANY LIGHTHOUSES ALSO INCLUDE BELLS, HORNS, OR EVEN CANNONS, THAT ARE USED AS FOG SIGNALS, DESIGNED TO WARN SAILORS ABOUT LOW VISIBILITY.    

D:  ANOTHER IMPORTANT FUNCTION OF LIGHTHOUSES IS TO BE A LANDMARK TO HELP SAILORS IDENTIFY WHERE THEY ARE.  ALL LIGHTHOUSES ARE UNIQUE.  SAILORS ARE ABLE TO IDENTIFY WHERE THEY ARE BY IDENTIFYING THE COLORS AND PATTERS ON THE LIGHTHOUSES THEY SEE.  

O:  ALL LIGHTHOUSES ALSO HAVE A UNIQUE LIGHT SIGNATURE.  FOR EXAMPLE, A LIGHTHOUSE MIGHT FLASH FOUR TIMES EVERY THREE SECONDS.  THAT WOULD HELP DISTINGUISH ITSELF FROM A LIGHTHOUSE THAT FLASHES JUST ONCE EVERY THREE SECONDS.  

D:  EVEN THOUGH MANY SAILORS NOW HAVE THE BENEFIT OF GPS TECHNOLOGY TO HELP NAVIGATE THEIR BOATS, LIGHTHOUSES ARE STILL VERY HELPFUL IN ANY SITUATIONS WHERE THE GPS ISN’T WORKING PROPERLY.  

O:  LIGHTHOUSES ARE ALL BEAUTIFUL AND SPECIAL IN THEIR OWN WAY.  MANY LIGHTHOUSES ARE MADE FROM DIFFERENT MATERIALS, THAT OFTEN INCLUDE THINGS THAT ARE AVAILABLE LOCALLY.  THAT MEANS THAT SOME LIGHTHOUSES ARE MADE OF BRICK, SOME FROM CONCRETE, SOME FROM STONE, SOME FROM WOOD, AND OTHERS ARE MADE FROM OTHER MATERIALS, LIKE IRON AND STEEL.

D:  SOME WERE BUILT ONSHORE, VERY CLOSE TO THE WATER, WHILE OTHERS ARE OFFSHORE, ON TOP OF SOMETHING LIKE A REEF.

O:  THE HEIGHTS OF LIGHTHOUSES ALSO VARY WIDELY.  IF THERE IS A LIGHTHOUSE ON TOP OF A TALL CLIFF, IT DOESN’T NECESSARILY NEED TO BE AS TALL AS A LIGHTHOUSE THAT IS LOCATED AT SEA LEVEL.  

D:  LIGHTHOUSES HAVE BEEN AROUND FOR MILLENNIA.  THE OLDEST LIGHTHOUSE THAT IS STILL IN OPERATION IS THE TOWER OF HERCULES, WHICH IS LOCATED IN NORTHERN SPAIN.  IT WAS BUILT IN THE FIRST CENTURY.  THAT’S ABOUT TWO THOUSAND YEARS AGO!  THE OLDEST LIGHTHOUSE THAT IS NO LONGER IN OPERATION IS THE PHAROS OF ALEXANDRIA LIGHTHOUSE, LOCATED IN EGYPT.  THAT LIGHTHOUSE WAS BUILT IN THE THIRD CENTURY BC, A FEW CENTURIES BEFORE THE TOWER OF HERCULES.  

O:  THE FIRST LIGHTHOUSES IN THE UNITED STATES WERE BUILT IN THE YEAR 1716.  BY 1900, THERE WERE MORE THAN ONE THOUSAND LIGHTHOUSES IN THE U.S.  TODAY, MICHIGAN HAS MORE LIGHTHOUSES THAN ANY OTHER STATE, WITH MORE THAN 120.  THE UNITED STATES NOW HAS MORE LIGHTHOUSES THAN ANY OTHER COUNTRY.    

D:  THE EARLIEST LIGHTHOUSES USED THE LIGHT FROM WOOD AND COAL FIRES TO ILLUMINATE THE NEARBY AREA.  THIS WASN’T VERY CONVENIENT, BECAUSE IT WOULD REQUIRE SOMEONE TO CARRY LOTS OF WOOD AND COAL TO THE TOP OF THE LIGHTHOUSE, OFTEN HUNDREDS OF STEPS.  

O:  AFTER THAT, THE LIGHT FROM CANDLES, GAS LAMPS, AND OIL LAMPS WERE USED.  THERE WERE A FEW PROBLEMS WITH THIS.  FIRST, IT TURNS OUT THAT THE LIGHT PROVIDED BY THESE FIRES WASN’T VERY BRIGHT.  ADDITIONALLY, USING FIRE FROM THESE SOURCES PRESENTED A VERY REAL DANGER TO THE LIGHTHOUSE ITSELF, IF THE FIRE WERE TO SPREAD.  

D:  WHEN LIGHTBULBS WERE INVENTED, MANY LIGHTHOUSES SWITCHED TO LIGHTBULBS TO PROVIDE LIGHT FOR THE SURROUNDING AREA.  LIGHTBULBS WERE MORE EFFECTIVE AND SAFER THAN FIRE, AND MANY LIGHTHOUSES STILL USE LIGHTBULBS TODAY.  

O:  HOW IN THE WORLD CAN A LIGHTBULB, OR EVEN A BUNCH OF LIGHTBULBS, PROVIDE A LIGHT POWERFUL ENOUGH TO HELP LIGHT UP THE OCEAN WATERS, PROVIDING NEEDED LIGHT FOR SAILORS?

D:  THEY WERE ABLE TO DO IT THANKS TO AN INGENIOUS INVENTION CALLED THE FRESNEL LENS.  ONCE IT WAS INVENTED IN 1822 BY FRENCH PHYSICIST AUGUSTIN-JEAN FRESNEL, THE FRESNEL LENS MADE IT POSSIBLE TO TURN A SMALL AMOUNT OF LIGHT INTO AN IMPRESSIVE BEAM OF LIGHT CAPABLE OF SHINING OVER DISTANCES OF 20 MILES OR EVEN MORE.  

O:  BUT, HOW DOES THE FRESNEL LENS WORK?

D:  MR. FRESNEL REALIZED THAT LIGHT WAS ENERGY THAT TRAVELLED IN WAVES.  HE WAS ABLE TO INVENT A LENS THAT CAN CAPTURE LIGHT WAVES AND ALSO SHINE THEM OVER LONG DISTANCES.  

O:  FRESNEL LENSES ARE MADE USING A DESIGN OF DIFFERENT SIZED GLASS RINGS.  THEY ARE ARRANGED TO TAKE THE LIGHT PRODUCED BY A LAMP OR LIGHTBULB AND REDIRECT THAT LIGHT HORIZONTALLY.  

D:  THE GLASS RINGS OF THE FRESNEL LENS HAVE DIFFERENT THICKNESSES, AND THEY ARE ARRANGED IN A WAY TO FOCUS ALL OF THE LIGHT TOWARDS THE CENTER OF THE LENS, RESULTING IN A LIGHT MUCH BRIGHTER THAN THE ACTUAL LIGHT EMITTED BY THE LAMP OR LIGHTBULB INSIDE THE LENS.  

O:  FRESNEL LENSES ARE SO INNOVATIVE, THAT THEY ARE ALSO USED FOR DIFFERENT THINGS TODAY, INCLUDING CAR HEADLIGHTS AND TRAFFIC LIGHTS.

D:  NOT TOO LONG AGO, LIGHTHOUSES REQUIRED A PERSON, CALLED A KEEPER, TO OPERATE THE LIGHTHOUSE.  THESE DAYS, ALMOST ALL LIGHTHOUSES ARE AUTOMATED.  THERE IS ONLY ONE LIGHTHOUSE IN THE UNITED STATES, LOCATED CLOSE TO BOSTON, MASSACHUSETTS, THAT IS STILL OPERATED BY A KEEPER.  IT IS CALLED BOSTON LIGHT, AND IT CAN BE FOUND ON LITTLE BREWSTER ISLAND.  IT’S THE SECOND WORKING LIGHTHOUSE IN THE UNITED STATES, BUILT IN 1783.  

O:  THE OLDEST WORKING LIGHTHOUSE IN THE UNITED STATES IS RIGHT HERE IN NEW JERSEY.  IT IS CALLED SANDY HOOK LIGHTHOUSE, AND IT WAS BUILT WAY BACK IN 1764.

D:  SO, LET’S LEARN MORE ABOUT THE LIGHT KEEPERS THAT HELPED OPERATE LIGHTHOUSES, BECAUSE THEIR JOB WAS REALLY FASCINATING.   

O:  MANY LIGHT KEEPERS HAD A CONNECTION TO THE SEA.  SOME OF THEM WERE FORMER FISHERMAN OR SAILORS.  IT WAS COMMON FOR LIGHT KEEPERS TO BE THE SON OR DAUGHTER OF A LIGHT KEEPER.  

D:  IN THE UNITED STATES, LIGHT KEEPERS MADE ABOUT $200 PER YEAR IN THE LATE 1800’S.  EVEN THOUGH THAT WAS A VERY LONG TIME AGO, IT WAS STILL A VERY LOW SALARY, CONSIDERING THE JOB IS SO DEMANDING.  

O:  THERE WERE TWO COMMON TYPES OF LIGHT KEEPERS.  IN SOME CASES, LIGHTHOUSES WERE OPERATED BY A HEAD KEEPER AND A FEW HELPERS.  THEY WORKED IN SHIFTS AND SPENT LOTS OF TIME AT THE LIGHTHOUSE AWAY FROM THEIR FAMILIES.  THIS WAS COMMON, ESPECIALLY WITH OFFSHORE LIGHTHOUSES.  

D:  IN OTHER CASES, KEEPERS LIVED WITH THEIR FAMILIES ON THE LIGHTHOUSE PREMISES.  THIS WAS THE MORE COMMON SCENARIO FOR ONSHORE LIGHTHOUSES.  

O:  THE KEEPER’S JOB WAS VERY DEMANDING.  THEY NEEDED TO REFILL THE GAS OR OIL IN THE LAMPS, CHANGE OR TRIM THE WICKS, CLEAN THE LENS OF DEBRIS AND SOOT, AND SOUND THE FOG SIGNAL.  THEY HAD TO KEEP THINGS VERY CLEAN TO ENSURE THAT EVERYTHING WORKED PROPERLY AND EVERYONE WAS SAFE.  

D:  KEEPERS WERE ALSO FREQUENTLY IN THE POSITION TO HELP PEOPLE WHO WERE IN DANGER.  IDA LEWIS WAS THE KEEPER OF THE LIME ROCK LIGHTHOUSE IN RHODE ISLAND FOR ABOUT 40 YEARS.  IN THAT TIME, SHE HELPED RESCUE MORE THAN A DOZEN SAILORS FROM DANGEROUS CONDITIONS IN THE WATER.    

O:  THERE ARE MORE THAN 18,600 LIGHTHOUSES WORLDWIDE, BUT LESS THAN 200 OF THEM ARE STILL OPERATED BY KEEPERS.  

D:  AND ONLY ONE OF THEM IS THE TALLEST LIGHTHOUSE IN THE WORLD, 22 FEET TALLER THAN THE NEXT TALLEST LIGHTHOUSE.  WHICH LIGHTHOUSE IS IT AND WHERE CAN IT BE FOUND?

O:  IT IS CALLED ILE VIERGE LIGHTHOUSE, AND IT CAN BE FOUND IN FRANCE.  IT IS MADE OF STONE, AND IT WAS BUILT IN 1902.  IT IS 271 FEET, OR 82.5 METERS.  THERE ARE ABOUT 400 STEPS TO GET TO THE TOP.  FRANCE HAS 3 OF THE 10 TALLEST LIGHTHOUSES IN THE WORLD.  

D:  THE SECOND TALLEST LIGHTHOUSE, CALLED LIGHTHOUSE OF GENOA, LOCATED IN GENOA, ITALY, IS SUPER NEAT BECAUSE IT IS ALSO VERY TALL, AND IT WAS BUILT CENTURIES BEFORE THE LIGHTHOUSE IN FRANCE, WAY BACK IN 1543.  YOU NEED TO CLIMB 365 STEPS TO GET TO THE TOP OF THE LIGHTHOUSE OF GENOA.  

O:  THE TALLEST LIGHTHOUSE IN THE UNITED STATES IS CAPE HATTERAS LIGHT, LOCATED IN NORTH CAROLINA.  IT IS MADE OF BRICK, AND IT STANDS 210 FEET, OR 64 METERS TALL.  IT WAS BUILT IN 1870, AND THERE ARE 268 STEPS FROM BOTTOM TO TOP.  

D:  HERE IS A BIZARRE STORY ABOUT A LIGHTHOUSE.  THERE WAS A LIGHTHOUSE IN SWEDEN, BUT IT WAS BUILT BY FINLAND.  THAT HAPPENED BECAUSE THE BUILDERS THOUGHT THE LAND BELONGED TO FINLAND, BUT IT TURNS OUT THAT IT WAS IN SWEDEN.   FINLAND DECIDED THEY NEEDED TO BUILD A LIGHTHOUSE ON AN ISLAND IN THE BALTIC SEA CALLED MARKET.  NOBODY LIVED ON MARKET, BUT SHIPS FREQUENTLY SANK CLOSE TO MARKET AS SAILORS TRIED TO AVOID THE ROCKY SHORES OF THE ISLAND.  IN 1885, A FINNISH ARCHITECT WAS ORDERED TO BUILD A LIGHTHOUSE ON MARKET, SO HE BUILT IT AT THE HIGHEST POINT OF THE ISLAND, WHICH WAS 10 FEET ABOVE SEA LEVEL.  THAT USUALLY MAKES SENSE, AS IT HELPS TO HAVE LIGHTHOUSES SHINE THEIR LIGHT FROM HIGH ABOVE SEA LEVEL, BUT HE DIDN’T CONSIDER THE FACT THAT THE  SPOT SELECTED, ALTHOUGH IT WAS STRATEGIC, WAS ACTUALLY ON THE SWEDISH SIDE OF THE BORDER.  AFTER IT WAS BUILT, FINLAND OPERATED THE LIGHTHOUSE AS IF IT BELONGED TO THEM, AND TENSIONS GREW BETWEEN FINLAND AND SWEDEN.  FINALLY, ALMOST A CENTURY AFTER IT WAS BUILT, FINLAND AND SWEDEN AGREED TO REDRAW THE BOUNDARIES OF MARKET ISLAND INTO A STRANGE Z SHAPE THAT OFFICIALLY PUT THE LIGHTHOUSE IN FINLAND.  WELL, THAT’S A WRAP FOR THIS WEEK’S EPISODE.

O:  227 - LIGHTHOUSES

D:  GREAT JOB OLIVIA, AND GREAT JOB MAXWELL, CYRUS, AND KAI FOR AN EPISODE TOPIC SUGGESTION THAT REALLY SHINES A LIGHT ON THE BEAUTIFUL STRUCTURES CALLED LIGHTHOUSES THAT WERE, AND STILL ARE, ESSENTIAL IN KEEPING MARITIME TRAVEL AS SAFE AS POSSIBLE.  BEFORE WE SAY GOODBYE FOR THE WEEK, WE HAVE A VERY SPECIAL LISTENER TO THANK.  

O:  WE WANT TO THANK ANA FOR THE 5 STAR REVIEW.

D:  IT SAYS “WOW.  YOU GUYS DO AN EXCEPTIONAL JOB OF MAKING PODCASTS FOR KIDS.”

O:  THANK YOU SO MUCH, ANA.  WE LOVE WHAT WE DO.  

D:  WE SURE DO, AND WE ARE GOING TO CONTINUE DOING IT NEXT SUNDAY, WHEN WE RETURN WITH A BRAND NEW EPISODE, AS WE’VE BEEN DOING EACH AND EVERY SUNDAY FOR FOUR AND A HALF YEARS.  JOIN US NEXT WEEK, WHEN WE WILL GET CURIOUS ABOUT CALORIES FOR LISTENERS IN FLORIDA.  AS ALWAYS, THANK YOU SO MUCH FOR LISTENING AND GETTING CURIOUS WITH US.