where he remained three years, at the expiration of which he resigned his charge, and accepted the Professorship of Mental and Moral Philosophy in Knox College, Toronto. His fondness for philosophical studies, and his wide acquaintance with philosophical literature, marked him out as peculiarly fitted for such a position. The sphere of his duties gradually widened, and in addition to Mental and Moral Philosophy and Logic, he soon had under his charge Exegetical Theology and the Evidences of Christianity--departments which are now in charge of Principal Caven and Professor Gregg. During his Professorship in Knox College, Professor Young contributed some remarkable papers on philosophical subjects to the pages of the _Canadian Journal_. One of these, containing a brief exposition of some points in the Hamiltonian philosophy of matter, reached the hands of Sir William Hamilton himself, the most eminent exponent of the Scottish philosophy. The latter was so impressed by the merits of the paper that he addressed to the author a long and very complimentary letter, in which he bore testimony to Professor Young's power of grasping and elucidating the most abstruse points in a philosophical system of which he was not the originator. Such a testimony, from such a source, must have been highly gratifying to Professor Young, for Sir William was not a man given to wasting his words, and would certainly not have written such a letter to a stranger had he not been very greatly impressed by the merits of the article in the _Journal_. Various other articles from his pen have from time to time appeared in the same periodical, and every one of them bears the stamp of a mind which, to parody Iago's well-known saying, is "nothing if not mathematical." While on the subject of authorship it may be mentioned that in 1854 a theological work from his pen was published at Edinburgh, under the title of "Miscellaneous Discourses and Expositions of Scripture." In 1862 he published in the _Home and Foreign Record_ a paper on "The Philosophical Principles of Natural Religion," which evoked much favourable comment alike from the religious and secular press at the time of its publication.