Madame de Pompadour was full of coquetries and amiability for the most dangerous adversaries of the old régime. La Tour’s pastel, which is at the Louvre, represents her seated in an armchair, her left arm resting on a table whereon are a globe and some books. The largest of these is the fourth volume of the Encyclopedia, that great arsenal of impiety, the prospectus of which had been launched by Diderot in 1750. Louis XV., always undecided, at first tolerated the gigantic collection of writings. Some years later (March, 1759) he revoked the privileges of the editors. A royal declaration of unwonted violence appeared at the same time against the authors, printers, publishers, and colporteurs of writings aimed against religion and royal authority. Almost every line proclaimed a death penalty. But a thousand means of eluding these Draconian laws were found, and most frequently authority closed its eyes. Voltaire cried enthusiastically: “Long life to the ministry of the Duke de Choiseul!” Nevertheless, warnings were not lacking to the favorite. She saw as clearly as Louis XV. himself the perils which the doctrines of the Encyclopedia made imminent for all kings. Madame du Hausset relates that a very curious anonymous letter was one day sent to the King and his mistress. As the author was bent on accomplishing his purpose, he had sent one copy to the lieutenant of police, sealed with this address: _For the King_; one with these words: _To Madame de Pompadour_, and still another to M. de Marigny. This letter, which greatly affected Louis XV. and his Marquise, struck them all the more forcibly because it was written in very respectful terms. Among other remarkable passages it contained the following prediction: “The Encyclopedists, under pretext of enlightening men, are sapping the foundations of religion. All sorts of liberty depend upon each other: the philosophers and the Protestants tend to republicanism as well as the Jansenists. The philosophers attack the trunk of the tree, the others some of its branches; but their efforts, without being concerted, will some day bring it down. Add to these the Economists, whose object is political liberty, as that of the others is liberty of worship, and the Government may find itself in twenty or thirty years undermined throughout and falling tumultuously into ruin.”