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.
Boxing glove
The use of hand protection in fighting contests undertaken for sport has been known since Ancient Greece. However, the gloves were very different from those of modern boxing, as was the sport itself. In Ancient Greece, it was common practice to tie strips of leather round the hands for protection. In Roman times, this developed into the gladiatorial cestus, with metal added to the gloves to inflict greater damage. The oldest surviving example of boxing gloves date to around 120 AD, coming in the form of two non-matching leather bands that were recovered from excavations at the Roman fort of Vindolanda. The brutality of the sport caused the boxing to be banned in AD 393.