“I can repeat to thee many a counsel of them of old, if thou shrink not back nor weary to learn of lowly cares.  Above all must the threshing-floor be levelled with the ponderous roller, and wrought by hand and cemented with clinging potter’s clay, that it may not gather weeds nor crack in the reign of dust, and be playground withal for manifold destroyers.  Often the tiny mouse builds his house and makes his granaries underground, or the eyeless mole scoops his cell; and in chinks is found the toad, and all the swarming vermin that are bred in earth; and the weevil, and the ant that fears a destitute old age, plunder the great pile of spelt.”

Perhaps some reader had been disposed hastily to say:  “What did you want with hooks out of doors?  Was not Nature enough?” No one who loves both books and Nature would ask that question, or need to have explained why a knapsack library is a necessary adjunct of a walking-tour.

For Nature and books react so intimately on each other, and, far more than one realizes without thought, our enjoyment of Nature is a creation of literature.  For example, can any one sensitive to such considerations deny that the meadows of the world are greener for the Twenty-third Psalm, or the starry sky the gainer in our imagination by the solemn cadences of the book of Job?  All our experiences, new and personal as they may seem to us, owe incalculably their depth and thrill to the ancestral sentiment in our blood, and joy and sorrow are for us what they are, no little because so many old, far-away generations of men and women have joyed and sorrowed in the same way before us.  Literature but represents that concentrated sentiment, and satisfies through expression our human need for some sympathetic participation with us in our human experience.

That a long-dead poet walking in the Spring was moved as I am by the unfolding leaf and the returning bird imparts an added significance to my own feelings; and that some wise and beautiful old book knew and said it all long ago, makes my life seem all the more mysteriously romantic for me to-day.  Besides, books are not only such good companions for what they say, but for what they are.  As with any other friend, you may go a whole day with them, and not have a word to say to each other, yet be happily conscious of a perfect companionship.  The book we know and love—­and, of course, one would never risk taking a book we didn’t know for a companion—­has long since become a symbol for us, a symbol of certain moods and ways of feeling, a key to certain kingdoms of the spirit, of which it is often sufficient just to hold the key in our hands.  So, a single flower in the hand is a key to Summer, a floating perfume the key to the hidden gardens of remembrance.  The wrong book in the hand, whether opened or not, is as distracting a presence as an irrelevant person; and therefore it was with great care that I chose my knapsack library.  It consisted of these nine books: