Monday, June 25, 2012

Red, White, and Blue


Gateway to a Shimmering City of White
Stupendous View from the Marin Headlands
We wanted to spend some time with family and friends back home so we rented a car in Sausalito for a day's drive to Portland and then on to Seattle the following day.  Before leaving San Francisco, we drove out to the Marin Headlands on the north side of the Golden Gate Bridge.  What a perfect day!  So often clouds blow in from the ocean and shroud “The City” with a blanket of gray.  We were thankful for the blue sky and stupendous views of the Golden Gate Bridge, Alcatraz Island, and the shimmering City Skyline.  From atop the Headlands we could see The City and its suburbs dressed in white, sandwiched between blue water and sky; the red bridge and majestic mountains stand like a mighty gateway.  Interestingly, San Francisco Bay was first sighted by the Spanish explorer Gaspar de Portola from the summit of the 1,200 foot Sweeney Ridge but he hadn't realized what he had found.  The first European to actually enter the Bay was Spanish explorer Juan de Ayala who arrived in 1775 on his ship the San Carlos and moored in a bay of Angel Island now known as Ayala Cove.  After stopping to take in the wonderful views, we continued our drive through the Marin Headlands out to Point Bonita Lighthouse.  As one might guess, the surrounding hillsides that make up the Headlands are peppered with old battery emplacements; and several Army camps, that once protected this important harbor, can still be seen near the entrance of the Bay.  The Bonita Lighthouse has stood watch over this gateway for more than 150 years.  Visiting the lighthouse is definitely a fun adventure, reached by hiking a trail out to Bonita Point then walking through a tunnel in the rock face and over a suspended foot bridge to the lighthouse perched on a rock pinnacle.  As we walked across the foot bridge looking down at the sea 300 feet below, the bridge began to bounce up and down.  Leonard, uncomfortable with heights, quickly made his way across, but I had to stop and take some pictures.  This unique lighthouse was the third lighthouse on the West Coast, completed in 1855 with a second-order Fresnel lens.  The Fresnel lens system was developed in 1822 by French physicist Augustin Fresnel; the system works with ground glass prisms arranged in rings around a light source.  Fresnel’s invention bends seventy percent of the outgoing bulb light and focuses it horizontally.  There are seven types of lenses or “orders” each different in size.  Navigators can distinguish one lighthouse from another because each lighthouse has its own pattern of light.  Point Bonita’s light switches on for three seconds, off for one.  In dense fog when the light signal cannot be seen, a sound system is activated.  Fog horns are as distinctive as light signals.  Point Bonita sends out two blasts every 30 seconds.  Most boaters today use electronic charts for navigation but lighthouses still serve as visual landmarks and aids to navigation.  We  look forward to being back on the boat and seeing many more sights in San Francisco upon our return from Seattle.
Bonita Point Lighthouse
Suspended Foot Bridge to Point Bonita Lighthouse
Cables Holding the Foot Bridge in Place
Cables Securely Anchored
A Long Way Down

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