David Richards (Dafydd Ionawr) Oxford, before going to teach at Oswestry grammar school. He then taught at the grammar school in Carmarthen before being appointed head of a free school in his native area. From 1800 to 1807, he taught in Dolgellau, where he remained until his death. David Richards (Dafydd Ionawr) David Richards (22 January 1751 – 12 May 1827), better-known by his bardic name Dafydd Ionawr, was a Welsh-language poet, born at Glanyrafon near Bryn-crug in the parish of Tywyn in Merionethshire (now Gwynedd), north-west Wales. He took an interest in poetry as a result of his acquaintance with Evan Evans (Ieuan
Month on the initial approximation that 2 lunations last 59 days: a 30-day full month followed by a 29-day hollow month — but this is only roughly accurate, and eventually needs correction by using larger cycles, or the equivalent of leap days. Additionally, the synodic month does not fit easily into the year, which makes accurate, rule-based lunisolar calendars complicated. The most common solution to this problem is the Metonic cycle, which takes advantage of the fact that 235 lunations are approximately 19 tropical years (which add up to not quite 6940 days). However, a Metonic calendar will drift against the