and his still longer series of original works and translations from the English in all branches of freethought--a really astonishing movement of intellectual energy despite the emotion attaching to the subject-matter--was for the most part prepared in the same essentially scientific temper. Of all the freethinkers of the period he had perhaps the largest range of practical erudition; [1126] and he drew upon it with unhasting and unresting industry. Imitating the tactic of Voltaire, he produced, with some assistance from Diderot, Naigeon, and others, a small library of anti-Christian treatises under a variety of pseudonyms; [1127] and his principal work, the famous System of Nature (1770), was put out under the name of Mirabaud, an actual person, then dead. Summing up as it does with stringent force the whole anti-theological propaganda of the age, it has been described as a "thundering engine of revolt and destruction." [1128] It was the first published atheistic [1129] treatise of a systematic kind, if we except that of Robinet, issued some years before; and it significantly marks the era of modern freethought, as does the powerful Essai sur les préjugés, published in the same year, [1130] by its stern impeachment of the sins of monarchy--here carrying on the note struck by Jean Meslier in his manuscript of half-a-century earlier. Rather a practical argument than a dispassionate philosophic research, its polemic against human folly laid it open to the regulation retort that on its own necessarian principles no such polemic was admissible. That retort is, of course, ultimately invalid when the denunciation is resolved into demonstration. If, however, it be termed "shallow" on the score of its censorious treatment of the past, [1131] the term will have to be applied to the Hebrew books, to the Gospel Jesus, to the Christian Fathers, to Pascal, Milton, Carlyle, Ruskin, and a good many other prophets, ancient and modern. The synthesis of the book is really emotional rather than philosophic, and hortatory rather than scientific; and it was all the more influential on that account. To the sensation it produced is to be ascribed the edict of 1770 condemning a whole shelf of previous works to be burnt along with it by the common hangman.