Besides his regular college duties, Professor Child had three distinct interests to which he devoted himself in leisure hours with all the energy of an ardent nature. The first of these, editing a complete edition of the old English ballads, was the labor of his life, and with it his name will always be associated, for it is a work that can neither be superseded nor excelled. He was the first to arouse English scholars to the importance of this, as may be read in the dedication of a partial edition taken from the Percy manuscripts and published in London in 1861. He recognized in them the true foundation of the finest literature of the modern world, and he considered them so much the better from the fact that they were not composed to be printed, but to be recited or sung. Matthew Arnold wrote in a letter from America: "After lecturing at Taunton, I came to Boston with Professor Child of Harvard, a very pleasant man, who is a great authority on ballad poetry," very warm praise, considering the source whence it came. Late in life Professor Child edited separate versions in modern English of some curious old ballads, and sent them as Christmas presents to his friends. It is not surprising that he should have been interested as well in the rude songs of the British sailors, which he heard on crossing the ocean. He was mightily amused at their simple refrain: "Haul in the bowlin', long-tailed bowlin', Haul in the bowlin' Kitty, O, my darlin'." "That rude couplet," he said, "contains all the original elements of poetry. Firstly, the anthropomorphic element; the sailor imagines his bowline as if it had life. Secondly, the humorous element, for the bowline is all tail. Thirdly, the reflective element; the monotonous motion makes him think of home,--of his wife or sweetheart,--and he ends the second line with 'Kitty, O, my darlin'.' I like such primitive verses much better than the 'Pike County Ballads,' a mixture of sentiment and profanity." Then he went on to say: "I want my children, when they grow up, to read the classics. My boy will go to college, of course; and he will translate Homer and Virgil, and Horace,--I think very highly of Horace; but the literal meaning is a different thing from understanding the poetry. Then my daughters will learn French and German, and I shall expect them to read Schiller and Goethe, Moliere and Racine, as well as Shakespeare and Milton. After that they can read what they like, but they will have a standard by which to judge other authors." He was afraid that the students wasted too much time in painting play-bills and other similar exercises of ingenuity, which lead to nothing in the end.