Pythagoras’ Monochord by Irini N. The ancient Greek mathematician, Pythagoras from Samos, was the first to discover the use of a single chord and its different notes. My musical instrument is based on his example as it has one chord placed on a piece of wood on which I marked ten lines vertically. I used these lines in order to show where the fingers should be placed but one could also use other spots so that the right notes come out properly. I used a couple of nails on both ends of the piece of wood (which I had already painted), in order to tie up carefully the fishing line used as a chord.