Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. The Most Reverend Cornelius Denvir D.D. (1791 1865) was an Irish Roman Catholic Prelate, mathematician, natural philosopher (physicist) and former Lord Bishop of Down and Connor. Dr Denvir was born in Ballywalter in County Down in 1791 and was educated as a young boy in Dr Nelsons 'classical school' in Downpatrick. He entered Maynooth College in 1808 and was ordained in 1814. After doctoral studies he taught Natural Philosophy and Mathematics at Maynooth. Among his students at Maynooth was the inventor and physicist Fr. Nicholas Callan, whom he introduced to electricity and magnetism.