Horizontal plane sundial from the Roman city of Aquileia (2nd century AD). The dial is formed by eleven hour lines, the shortest of which is the noon line which runs from north to south and is the meridian. A hole for the gnomon lies at the southern end of this line. The curve nearest the gnomon hole traces the shadow track for the day of the summer solstice, the furthest curve is the shadow track for the winter solstice. The straight east-west line between these two curves marks the shadow track of the equinox. Around the perimeter are engraved the names of the twelve winds, for example, Boreas, Desolinus, Auster and Favonius, indicating the direction from which they blow. This Wind Rose is the predecessor to the Compass Rose. The name of the maker, M. Anstitius Euporus is inscribed within the dial.