To further their propaganda without at the same time attracting the notice of the civil authorities the rationalist party had recourse to various devices. Pamphlets and books were published, professedly descriptive of manners and customs in foreign countries, but directed in reality against civil and religious institutions in France. Typical examples of this class of literature were the Persian Letters of Montesquieu, A Description of the Island of Borneo by Fontanelle, The Life of Mohammed by Henri de Bouillon Villiers, and a Letter on the English from the pen of Voltaire. The greatest and most successful work undertaken by them for popularising their ideas was undoubtedly the Encyclopedie.