Joseph Priestley was born in 1733 at Fieldheads, about six miles from Leeds. His father, a maker and dresser of woollen cloth, lost his wife when his son Joseph was about six years of age; and being poor, his sister, Mrs. Keighley, offered to bring up the boy. The early associations of the lad were closely connected with dissent; and after some time spent at a public school in the neighbourhood, he was sent, in 1752, to the Academy at Daventry, in which he was trained for the ministry. There he gained some knowledge of mechanics and metaphysics, and also acquired some acquaintance with Chaldee, Syriac, and Arabic, besides being a competent French and German scholar. After leaving the Academy, he settled at Needham in Suffolk, as assistant in a small meeting-house, where his income was not over £30 a year. His views were, however, too liberal for his hearers; and after some years he moved to Nantwich in Cheshire, where he preached and also taught a school. Here his income was improved, though still miserably small; yet he managed to buy some books, a small air-pump, and an electrical machine. He subsequently removed to Warrington, being employed there in teaching and in literary work; among his writings was a _History of Electricity_, which first brought him into notice, and which procured for him the degree of LL.D. of Edinburgh, thus giving him a right to the title of Doctor, by which he was always afterwards known. At Warrington, too, he married. We next find him being asked in 1767 to take the pastorship of Millhill Chapel at Leeds, a call which he accepted. The chapel was next door to a brewery, and this circumstance first induced him to take up the subject of the chemistry of gases, which has made his name famous. Here too he published his _History of Discoveries relative to Light and Colours_. After six years spent at Leeds, he became librarian to the Earl of Shelburne (afterwards Marquis of Lansdowne) and travelled with him on the Continent. While with Lord Shelburne he published the first three volumes of _Experiments on Air_, and carried out investigations which were recorded in a fourth volume, published after his removal to Birmingham. After some years spent in this way, he was pensioned off, and settled as minister of a meeting-house in Birmingham, where he employed his time partly in theological controversy, and partly in prosecuting researches in chemistry. He published during this period another three volumes giving a description of his experiments on air, and communicated several papers to the _Philosophical Transactions_ of the Royal Society, of which he had been made a Fellow. Towards the year 1790 he was so unfortunate as to attack Burke’s book on the French Revolution; and this had the effect of rousing popular opinion against him, more especially that of the local clergy, whose political views he had frequently opposed. During the riots which took place at Birmingham