His early inclination for study induced his father to send him to the College of La Flèche when he was only eight years old. We have the accounts of extraordinary progress which are usually related of men after they have become distinguished; but what is not so common, we find that he was allowed to keep his bed in the morning as long as he pleased, partly from the weakness of his health, and partly because he was observed to be of a meditative turn. We mention this because it afterwards became his usual habit to study in bed; and certainly some parts of his philosophy bear the marks of it. He left La Flèche in eight years and a half, with great reputation, and a disgust for all books and methods then in use. He was sent to Paris at the age of seventeen, under the care of a servant, and fell into the fashionable vice of gambling; but at the same time he cultivated the acquaintance of Mydorge[9] and Mersenne. He finally became disgusted with his favourite pursuit, hired a solitary house in the Fauxbourg St. Germain, and resumed his studies. Footnote 9: To explain in the briefest terms who these and other friends of Des Cartes were, would make us exceed the prescribed bounds. Our reader must be content to be referred to a biographical dictionary for these and others not known, except to mathematicians. At the age of twenty-one, he enlisted as a volunteer under the Prince of Orange. At Breda, the solution of a problem introduced him to Beekman. Here he wrote his ‘Treatise on Music,’ of which the latter (to whom it had been entrusted) gave himself out as the author. In 1619, he enlisted as a volunteer under the Duke of Bavaria; and while thus engaged, he tells us he laid the foundations of his philosophy (November 10); after three wonderful dreams. Quitting the service he was engaged in, after having been present at the siege of Prague, he travelled till the end of 1619. He then returned to Paris, where it was believed he was a Rosicrucian, and his continual presence in public was necessary to repel the suspicion. At this time he appears to have laid the foundation of his mathematical methods. After travelling into Italy, he settled again at Paris, and we now find him in habits of friendship with Beaune (afterwards his commentator), Morin, Frenicle, and others, and occupying himself with practical optics. In 1628, he served at the siege of Rochelle.