1968 was a big year for me. I turned 15 and I went on a date, my first, with a girl who would later–45 years later, become my late-life partner and constant companion, road trips included. But that is another story. Earlier in that big year I experienced my very first road trip adventure.
My uncle Bob had completed his medical school training and had been accepted for the next stage on his path towards becoming a practicing physician: an internship at Oakland Medical Center. In 1968, Oakland California was a long way from Minneapolis Minnesota. Yes, an expensive plane ride could get you there in three hours, but if you needed to bring more than a weight-limited suitcase, a three-day overland drive was required.
And Bob was fully ready for it, having recently acquired a 1968 model year Ford Mustang convertible, into which he packed the possessions that would support him for the next year in a remote setting. The car was symbolic, a vehicle to take him to that next phase of his career. It was freeing. With the top down, the wind in his hair evoked that sense of traveling to far off destinations holding unknown new experiences. It was a big year for him too.
There was a second wide spot in the road at the south end of the playa; we parked and continued our explorations. This time we found stones sitting on the surface of the lakebed. There were not many, and we had to hike a mile or so to find them. Some sat happily contemplating their position in the uniform semi-infinite plane of mud cracks. Others showed a faint trail of disturbed, and now solidified mud, leading to their current position. These were the famous sailing stones!
Life highlights are those you can list on a single hand. They are indelible events that exceed the normal range of our experience. They may include a first kiss, the birth of a child, recognition of a career accomplishment, or the challenging hike to reach a beautiful mountain pass. This is the story of adding one more of those outlier life experiences to my list.
Years ago, I had read about the geologic mystery of the “sailing stones” on the Racetrack Playa in Death Valley. Death Valley is an intriguing place and not just because of its ominous (and deserved) name. It is a geology and biology classroom, displaying the impacts of volcanoes intruding on sedimentary layers that have been shape-shifted into ribbons of colorful escarpments with water and wind-eroded features. Somehow, the valley has fallen below sea level, and the water, when there is water, dissolves minerals from the mountains and finds its way to the bottom, where it evaporates and leaves the residue behind as a salt flat.
In the spring, the water also nourishes an intense flowering of desert plants, desperate to reproduce. For a few brief weeks, colorful plants and flowers adorn the roadsides and cover the otherwise barren hills. I have been to Death Valley during this season, during a “superbloom” following an unusually wet winter. It was a stunning display of flowers in this otherwise arid and nonviable setting, something I had never expected to see. As impressive as this floral show was, I had really hoped to visit the famous sailing stones on the playa.
My printed tile map. It identifies the fat and skinny rhombus tiles so that I knew how many to make and how to place them. It was generated based on a simulation of an edge length of 250mm and a gap width of 6mm, adding up to a nice binary number.
I suspended this project in order to go on a roadtrip to capture pictures of the night sky in the beautiful deserts of the Southwest. I am currently working on them, and hope to share them soon, but the Penrose tile floor project carries a higher priority—we want our screen porch back while it is still summer!
Having prepared my tiles to the best accuracy I could coax from my woodworking tools, I now faced how to place them on the floor. As before, I considered the advice from Ken Adelman, who recommended “dis-aligning” the pattern from the rectangle of the room, to avoid difficult or awkward-looking tile fragments at the edges. He also recommended identifying a center point and creating reference lines radiating at angles that match the pentagonal symmetries of the tiling.