Such a book has Carlyle's Sartor Resartus been to many; or the play of Hamlet, read for the first time; or the Faust of Goethe; or the Confessions of St. Augustine; or an essay of Emerson; or John Ruskin; or the Divine Comedy of Dante; or even an exquisite work of fiction, like John Halifax, or Henry Esmond. What the book is that works such miracles is never of so much importance as the epoch in the mind of the reader which it signalizes. It were vain to single out any one writer, and say to all readers--"Here is the book that must indispensably be read;" for the same book will have totally different effects upon different minds, or even upon the same mind, at different stages of development. When I have been asked to contribute to the once popular _symposia_ upon "Books which have helped me,"--I have declined, for such catalogues of intellectual aids are liable to be very misleading. Thus, if I were to name the book which did more than most others for my own mind, I should say that it was the Emile of Rousseau, read at about the age of seventeen. This work, written with that marvellous eloquence which characterises all the best productions of Jean Jacques, first brought me acquainted with those advanced ideas of education which have penetrated the whole modern world. Yet the Emile would probably appear to most of my readers trite and common-place, as it would now to me, for the reason that we have long passed the period of development when its ideas were new to us. But the formative power of books can never be over-rated: their subtle mastery to stimulate all the germs of intellectual and moral life that lie enfolded in the mind. As the poet sings-- "Books are not seldom talismans and spells."