Josiah Wedgwood was a potter, not an author. He was famous for founding the Wedgwood pottery company and revolutionizing the ceramics industry in the 18th century. He did not write any books or published works.
You might be thinking of his descendants, like Josiah Wedgwood II (who wrote "The Life of Josiah Wedgwood" - but he's not the Josiah Wedgwood you are likely thinking of).