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].