Unfortunately for seagoing vessels the world over, it was time to move on. I slid the aluminium back into its place under my outer clothing and walked on until the light began to fade and we set up camp for another night. The sun took a long time to sink behind the westernmost mountain, and I was distracted from further experimentation as I calculated why the sunset might appear faster at latitudes closer to zero. Once we’d eaten, encircled our camp with a low fire, and cleared our sleeping ground of rocks while not-so-secretly also checking for snakes and spiders, it was too late for me to indulge in further theorising.
Several days passed in a similar fashion, and we cut across country to meet the course of a different river more conducive to our direction. My mind was half occupied wit
