While Grimm was amusing himself at Madame d’Epinay’s country house, Diderot was working at the literary correspondence which Grimm was accustomed to send to St. Petersburg and the courts of Germany.  While Grimm was hunting pensions and honorary titles at Saxe-Gotha, or currying favour with Frederick and waiting for gold boxes at Potsdam, Diderot was labouring like any journeyman in writing on his behalf accounts and reviews of the books, good, bad, and indifferent, with which the Paris market teemed.  When there were no new books to talk about, the ingenious man, with the resource of the born journalist, gave extracts from books that did not exist.[238] When we hear of Paris being the centre of European intelligence and literary activity, we may understand that these circular letters of Grimm and Diderot were the machinery by which the light of Paris was diffused among darker lands.  It is not too much to say that no contemporary record so intelligent, so independent, so vigorous, so complete, exists of any other remarkable literary epoch.

The abbe Raynal, of whom we shall have more to say in a later chapter, had founded this counterpart of a modern review in 1747, and he sent a copy of it in manuscript once a month to anybody who cared to pay three hundred francs a year.  In 1753 Raynal had handed the business over to Grimm, and by him it was continued until 1790, twelve years beyond the life of Voltaire and of Rousseau, and six years after the death of the ablest, most original, and most ungrudging of all those who gave him their help.

An interesting episode in Diderot’s life brought him into direct relations with one of the two crowned patrons of the revolutionary literature, who were philosophers in profession and the most arbitrary of despots in their practice.  Frederick the Great, whose literary taste was wholly in the vein of the conventional French classic, was never much interested by Diderot’s writing, and felt little curiosity about him.  Catherine of Russia was sufficiently an admirer of the Encyclopaedia to be willing to serve its much-enduring builder.  In 1765, when the enterprise was in full course, Diderot was moved by a provident anxiety about the future of his daughter.  He had no dower for her in case a suitor should present himself, and he had but a scanty substance to leave her in case of his own death.  The income of the property which he inherited from his father was regularly handed to his wife for the maintenance of the household.  His own earnings, as we have seen, were of no considerable amount.  There are men of letters, he wrote in 1767, to whom their industry has brought as much as twenty, thirty, eighty, or even a hundred thousand francs.  As for himself, he thought that perhaps the fruit of his literary occupations would come to about forty thousand crowns, or some five thousand pounds sterling.  “One could not amass wealth,” he said pensively, and his words are of grievous generality