Arc in the Sky

I was thinking of you the entire way back, on the train. As we rumbled through the Scottish countryside, I stared longingly out the window, rolling green hills so far as I could see. And then we came upon it.
   The entire horizon was filled with a great arc in the sky: a rainbow. From the very left periphery of my view through the window, it began kissing the ground, softly, and rising, reaching higher, surpassing the hills, touching the thin white clouds.
   Every person in the car was glued to the window, in awe. Some were trying to take photographs. I took a deep breath. My eyes followed where the curve of colour descended, glittering and beautiful until it reached the ground and dissolved into the grass.
   The rainbow stared back at me. I didn’t know how to respond, so I sat agape. And then, the trick of the light, the rare combination of sunlight, water vapour, and angle of viewing; it all fell apart. Suddenly, every person in the train car was staring out the window, and there was naught looking back.
   And I thought of your last words to me, that we’d had good times, but that now it was over.