The copy before us, of Mr. Goodyear's work upon "Gum-Elastic and its Varieties," presents at least something unique in the art of book-making. It is self-illustrating; inasmuch as, treating of India-rubber, it is made of India-rubber. An unobservant reader, however, would scarcely suspect the fact before reading the Preface, for the India-rubber covers resemble highly polished ebony, and the leaves have the appearance of ancient paper worn soft, thin, and dingy by numberless perusals. The volume contains six hundred and twenty pages; but it is not as thick as copies of the same work printed on paper, though it is a little heavier. It is evident that the substance of which this book is composed cannot be India-rubber in its natural state. Those leaves, thinner than paper, can be stretched only by a strong pull, and resume their shape perfectly when they are let go. There is no smell of India-rubber about them. We first saw this book in a cold room in January, but the leaves were then as flexible as old paper; and when, since, we have handled it in warm weather, they had grown no softer. Some of our readers may have heard Daniel Webster relate the story of the India-rubber cloak and hat which one of his New York friends sent him at Marshfield in the infancy of the manufacture. He took the cloak to the piazza one cold morning, when it instantly became as rigid as sheet-iron. Finding that it stood alone, he placed the hat upon it, and left the articles standing near the front door. Several of his neighbors who passed, seeing a dark and portly figure there, took it for the lord of the mansion, and gave it respectful salutation. The same articles were liable to an objection still more serious. In the sun, even in cool weather, they became sticky, while on a hot day they would melt entirely away to the consistency of molasses. Every one remembers the thick and ill-shaped India-rubber shoes of twenty years ago, which had to be thawed out under the stove before they could be put on, and which, if left under the stove too long, would dissolve into gum that no household art could ever harden again. Some decorous gentlemen among us can also remember that, in the nocturnal combats of their college days, a flinty India-rubber shoe, in cold weather, was a missive weapon of a highly effective character.