Guidonian hand
In Medieval music, the Guidonian hand was a mnemonic device used to assist singers in learning to sight-sing. Some form of the device may have been used by Guido of Arezzo, a medieval music theorist who wrote a number of treatises, including one instructing singers in sightreading. The hand occurs in some manuscripts before Guido's time as a tool to find the semitone; it does not have the depicted form until the 12th century. Sigebertus Gemblacensis in 1105–10 did describe Guido using the joints of the hand to aid in teaching his hexachord. The Guidonian hand is closely linked with Guido's new ideas about how to learn music, including the use of hexachords, and the first known Western use of solfege.
Paolo Guidotti
His flying apparatus was contrived with whalebone and down feathers, and the episode is described as thus:But his most extraordinary whim was that of flying. He contrived wings of whalebone in the most ingenious manner, which he covered with down, and giving them sufficient folds by means of springs, joined them under his arms; and having made a number of trials in private, determined at length to make a public exhibition. He ascended from one of the eminencies of Lucca, and was carried for about a quarter of a mile; but his wings not being able to support him any longer, he fell through a roof into a chamber, and broke his thigh. Giambatista Dante, of Perugia, had also the same whim, and the same fate. Oliver of Malmesbury, an English Benedictine, and good mechanic, in 1060, Bacville, a Jesuit of Padua, a Theatine of Paris, and a number of others, have all been thus desirous of soaring into the regions of air, and have all been equally successful. This, however, cannot be properly termed flying, but only an easier and slower method of falling. A flight can only be applied to the feat of the Padre Andrea Grimaldi of Civitavecchia, who returned from the East Indies with a wonderful machine of his own invention, in the form of an eagle; seated across which he was borne from Calais to London, 1751, making seven leagues an hour, directing his flight either higher or lower, as he pleased. This fact is most seriously recorded in the "Modern History." It is possible that posterity may consider this invention much to our honour. .
Francesco Milizia goes on to conclude that had Guidotti not attached himself to so many things, "he might have been a good artist...he was, it may be supposed, singular in his thoughts and reasoning."