Four years ago last March this book appeared in England, published by Longman; a thin octavo, exciting little attention there, and scarcely more on this side the water, where the best English books have of late years found their first appreciation. The first notice of it printed in this country, so far as we know, appeared in the "Harvard Magazine" for June, 1855,--a publication so obscure, that, to most readers of the ATLANTIC, this will be their first knowledge of its existence. About two years later, Part II appeared in England, and then both books were reviewed in the "Christian Examiner"; yet, to all intents and purposes, this new edition is a new book, and we shall treat it as such. We have as yet a reprint of Part I. only, but we trust the publishers will soon give us the other,--"The Practice of Morals,"--which, if less valuable than this, is still so much better than most works of its kind as to demand a republication. The author--a woman--(for, to the shame of our _virile secus_ be it said, a woman has written the best popular treatise on Ethics in the language)--divides her First Part into four chapters:-- I. What Is the Moral Law? II. Where the Moral Law is found. III. That the Moral Law can be obeyed. IV. Why the Moral Law should be obeyed. This, as will be seen, is an exhaustive analysis. To the great question of the first chapter, after a full discussion, she gives this answer:-- "The Moral Law is the resumption of the eternal necessary Obligation of all Rational Free Agents to do and feel those Sentiments which are Right. The identification of this law with His will constitutes the Holiness of the Infinite God. Voluntary and disinterested obedience to this law constitutes the Virtue of all finite creatures. Virtue is capable of infinite growth, of endless approach to the Divine nature and to perfect conformity with the law. God has made all rational free agents for virtue, and all worlds for rational free agents. _The Moral Law, therefore, not only reigns throughout His creation_, (all its behests being enforced thereon by His omnipotence,) _but is itself the reason why that creation exists_."--pp. 62-63. This is certainly good defining, and the passage we have Italicized has the true Transcendental ring. Indeed, the book is a system of Kantian Ethics, as the author herself says in her Preface; and the tough old Königsberg professor has no reason to complain of his gentle expounder. Unlike most British writers,--with the grand exception of Sir William Hamilton, the greatest British metaphysician since Locke and Hume,--she _understands_ Kant, admires and loves him, and so is worthy to develop his knotty sublimities. This alone would be high praise; but we think she earns a more original and personal esteem. The question of the second chapter she thus answers:--