articles. He was therefore obliged to provide much of the journal's content himself (this material became the basis for many of his later theological and metaphysical works). After only a few years, due to a lack of funds, he was forced to cease publishing the journal. He revived it in 1784 with similar results. Defender of Dissenters and political philosopher Many of Priestley's political writings supported the repeal of the Test and Corporation Acts, which restricted the rights of Dissenters. They could not hold political office, serve in the armed forces, or attend Oxford and Cambridge unless they subscribed to the Thirty-nine Articles of the Church of England. Dissenters repeatedly petitioned Parliament to repeal the Acts, arguing that they were being treated as second-class citizens. Priestley's friends, particularly other Rational Dissenters, urged him to publish a work on the injustices experienced by Dissenters; the result was his Essay on the First Principles of Government (1768). An early work of modern liberal political theory and Priestley's most thorough treatment of the subject, it—unusually for the time—distinguished political rights from civil rights with precision and argued for expansive civil rights. Priestley identified separate private and public spheres, contending that the government should have control only over the public sphere. Education and religion, in particular, he maintained, were matters of private conscience and should not be administered by the state. Priestley's later radicalism emerged from his belief that the British government was infringing upon these individual freedoms. Priestley also defended the rights of Dissenters against the attacks of William Blackstone, an eminent legal theorist, whose Commentaries on the Laws of England (1765–69) had become the standard legal guide. Blackstone's book stated that dissent from the Church of England was a crime and that Dissenters could not be loyal subjects. Furious, Priestley lashed out with his Remarks on Dr. Blackstone's Commentaries (1769), correcting Blackstone's interpretation of the law, his grammar (a highly politicised subject at the time), and history. Blackstone, chastened, altered subsequent editions of his Commentaries: he rephrased the offending passages and removed the sections claiming that Dissenters could not be loyal subjects, but he retained his description of Dissent as a crime. Natural philosopher: electricity, Optics, and carbonated water Although Priestley claimed that natural philosophy was only a hobby, he took it seriously. In his History of Electricity, he described the scientist as promoting the "security and happiness of mankind". Priestley's science