Pinule A pinule (also often described as a sighting pinhole) is a small pin with a pin-sized hole in it. Resembling the site of a gun, it is fixed upon a pre-telescopic astronomical instrument and enables the observer to make an accurate pointing. For an example of a pinule, see the brass and silvered brass mechanical equinoctial dial by mathematical instrument maker Thomas Wright around 1735 (coming soon to Clocktime).
