Sant'Agostino Altarpiece Sant'Agostino Altarpiece The Sant'Agostino Altarpiece is a painting by Perugino, produced in two stages between around 1502 and 1512 and then around 1513 to 1523. The altarpiece's 28, 29 or 30 panels were split up during the Napoleonic suppression of religious houses - most of its panels are now in the Galleria Nazionale dell'Umbria in Perugia. It is notable as the painter's last masterwork before he moved into his late phase producing more provincial commissions. It was commissioned by the monks of Sant'Agostino church in Perugia. The first phase included the artist's peak years and the crisis from 1508 onwards
Hinged dissection Hinged dissection A hinged dissection, also known as a swing-hinged dissection or Dudeney dissection, is a kind of geometric dissection in which all of the pieces are connected into a chain by "hinged" points, such that the rearrangement from one figure to another can be carried out by swinging the chain continuously, without severing any of the connections. Typically, it is assumed that the pieces are allowed to overlap in the folding and unfolding process; this is sometimes called the "wobbly-hinged" model of hinged dissection. The concept of hinged dissections was popularised by the author of mathematical puzzles, Henry Dudeney.