IX. After having been near a year in France, he returned to Holland. He had the greatest pleasure in his journey: one thing only was wanting to his satisfaction, a sight of the celebrated M. de Thou, the person among all the French whom he most esteemed. He had fought to get acquainted with that great man; but did not succeed. As soon as he returned to Delft, he wrote him[26] that he had been a year in France; had the pleasure of seeing a fine kingdom, a great king, very valuable noblemen, but had the mortification of not seeing him; that he would endeavour to repair this misfortune by his letters; and that he took the liberty to present him with a book he had just dedicated to the Prince of Conde. This Letter was extremely well received by the President; and from that time to the death of M. de Thou, notwithstanding the disproportion of their age and fame, a most intimate correspondence subsisted between them. Grotius sent him, July 4, 1600,[27] the _Epithalamium_ he had written on the Marriage of King Henry IV. with Mary of Medicis. Mention was made in it of the Massacre on St. Bartholomew's day: this was an invidious subject; but the author, after consulting Scaliger, thought he could not dispense with recalling the remembrance of that horrid scene. He was in doubt whether he ought to publish this piece: he asked the President de Thou's advice; and till he had his answer, shewed the verses to none. Whether it was that M. de Thou advised him to suppress them, or that he took this step of himself[28] because there were several facts in the _Epithalamium_ not strictly true, it is not to be found in the collection of his _Poems_. He intended to dedicate some Work to the President, as a public testimony of his profound esteem for that excellent Magistrate, whom he regarded as the greatest Man of his age[29]. M. de Thou soon perceived the great merit of young Grotius; and had the highest affection for him[30]. They corresponded by Letter whilst the President lived: Grotius sent him memoirs[31] for his _History_, and hints relating to the lives and deaths of illustrious men in the United Provinces. It was a thing infinitely pleasing, and at the same time extremely honorable to a youth between seventeen and eighteen, to be most intimately connected with one of the greatest men of his time, already advanced in years, who filled a post of much eminence, and whom all Europe beheld with admiration. The friendship and esteem of such a personage is the highest encomium.