The third suggestion is that a common disposition to question a long term for copyright, on the ground that a short term suffices for patents, is based upon false analogy. Literary and artistic productions and useful inventions may be equally the creations of the mind, and they are coupled in the Constitution; but they are coupled, it is pointed out, only as deserving protection. Their character, and the duration of the protection required by each, may be very different. It is alleged to be very different. The monopoly is different; the returns to the creator are different, and the interests of the public are different in the two cases. The monopoly by patent in an invention is a complete monopoly of the idea. The monopoly by copyright in a literary or artistic work is a monopoly merely of the particular expression of the idea. The inventor's exclusive control of his idea, it is said, may bar innumerable other inventions, applications of his idea, of importance to the public, while the author's or artist's exclusive control of his particular expression bars no one except the mere reproducer. The returns to an inventor are apt to be quick; the returns to an author are apt to be slow, and the slower in proportion to the serious character of his book, if a book. The returns to a successful inventor are apt to be large; the returns to even a successful author or artist are not apt to be more than moderate. Then the idea, it is said, covered by an invention or discovery, may concern the essential welfare, even the lives, of the community, and should be freely available at the earliest possible moment not unjust to the creator of it. Now, it is remarked that no particular book, at least none currently copyrighted to-day, can be said to be essential to the welfare or protection of the community. Many a man's pleasure may be enhanced by it, some men's profit; but no man's essential welfare depends upon it, and no man's life, save, perhaps, the author's own. I communicate those suggestions as having been pressed upon us.