In the summer 2007, I boarded a ferry headed to Spectacle Island in Boston. Though I had been living in the city for four years, I had never explored the series of small islands known as the Harbor Islands just off shore. Upon arrival on the island, I put on a set of headphones and began traversing the landscape. Playing over the headset was Terri Rueb’s Core Sample, a sound installation guided by GPS technology, and as I walked, I listened to the palimpsestic soundtrack of the island’s history: the blaring of foghorns, snippets of oral testimonies, the hissing of natural gas, the crunching of rocks.