In this era of spaceships, iPads, and nuclear bombs, it's easy to forget the wonder of the simple technologies of the past. Take the telescope. Just think about how strange it is that you take a piece of material, stick it into a tube, and suddenly can see the moon in close-up detail. How crazy is that? I was reminded of this minor glory reading Roger Bacon's 17th century book, Discovery of the Miracles of Art and Nature. Check out his description of how telescopes (and microscopes) work.
We can so shape transparent substances, and so arrange them with respect to our sight and objects, that rays can be broken and bent as we please; and thus from an incredible distance we may read the smallest letters and number the grains of dust and sand, on account of the greatness of the angle under which we see them; and we may manage so as hardly to see bodies when near to us, on account of the smallness of the angle under which we cause them to be seen; for vision of this sort is not a consequence of distance, except as that affects the magnitude of the angle. And thus a boy may seem a giant, and a man a mountain.
"And thus a boy may seem a giant, and a man a mountain." Now that must have been a shock to the system. We didn't even know what light was really, and yet we knew it could be transformed in this crazy ways. Just worth keeping in mind while we ooh and ahh over the the latest mobile operating system.