by means short of constructing, or purchasing the things authorized. A temporary use of a suitable site or building may possibly be obtained with, or without hire. Besides; why may not congress purchase, or erect a post-office building, and buy the necessary land, if it be in their judgment advisable? Can there be a just doubt, that a power to establish post-offices includes this power, just as much, as a power to establish custom-houses would to build the latter? it not be a strange construction to say, that the abstract office might be created, but not the officina, or place, where it should be exercised? There are many places peculiarly fit for local post-offices, where no suitable building could be found. And, if a power to construct post-office buildings exists, where is the restraint upon constructing roads? Would if § 556. But whatever be the extent of the power, narrow or large, there will still remain another inquiry, whether it is an exclusive power, or concurrent in the states. This is not, perhaps, a very important inquiry, because it is admitted on all sides, that it can be exercised only in subordination to the power of congress, it be concurrent in the states. A learned commentator deems it concurrent, inasmuch as there seems nothing in the constitution, or in the nature of the thing itself, which may not be exercised by both governments at the same time, without prejudice or interference; but subordinate, because, whenever any power is expressly granted to congress, it is to be taken for granted, that it is not to be contravened by the authority of any particular state. A state might, therefore, establish a postroad, or post-office, on any route, where congress had not established any. On the other hand, another learned commentator is of opinion, that the power is exclu sive in congress, so far as relates to the conveyance of letters. Hitherto the question has been purely speculative; and it cannot now be important to discuss it. It is highly improbable, that any state will attempt any exercise of the power, considering the difficulty of carrying it into effect, without the co-operation of congress. CHAPTER XIX. POWER TO PROMOTE SCIENCE AND USEFUL ARTS. § 557. THE next power of congress is, "to promote "the progress of science and the useful arts, by secur"ing, for limited times, to authors and inventors the "exclusive right to their respective writings and dis"coveries." § 558. This power did not exist under the confederation; and its utility does not seem to have been questioned. The copyright of authors in their works had, before the revolution, been decided in Great Britain to be a common law right; and it was regulated and limited under statutes passed by parliament upon that subject. The right to useful inventions seems, with equal reason, to belong to the inventors; and, accordingly, it was saved out of the statute of monopolies in the reign of King James the First, and has ever since been allowed for a limited period, not exceeding fourteen years. It is doubtless to this knowledge of the common law and statuteable rights of authors and inventors, that we are to attribute this constitutional provision. It is beneficial to all parties, that the national government should possess this power; to authors and inventors, because, otherwise, they would be subjected to the varying laws and systems of the different states on this subject, which would impair, and might even destroy the value of their rights; to the public, as it will promote the progress of science and the useful arts, and admit the people at large, after a short interval, to the full possession and enjoyment of all writings and inventions without restraint. In short, the only boon that could be offered to inventors to disclose the secrets of their discoveries, would be the exclusive right and profit of them, as a monopoly, for a limited period. And authors would have little inducement to prepare elaborate works for the public, if the publication of them would be at a large expense, and, as soon as they were published, there would be an unlimited right of depredation and piracy of their copyright. The states could not separately make effectual provision for either of the cases; and most of them, at the time of the adoption of the constitution, had anticipated the propriety of such a grant of power, by passing laws on the subject, at the instance of the continental congress. 559. The power, in its terms, is confined to authors and inventors; and cannot be extended to the introducers of any new works or inventions. This has been thought by some persons of high distinction to be a defect in the constitution. But perhaps the policy of further extending the right is questionable; and, at all events, the restriction has not hitherto operated as any discouragement of science or the arts. It has been doubted, whether congress has authority to decide the fact, that a person is an author or inventor in the sense of the constitution, so as to preclude that question from judicial inquiry. But, at all events, such a construction ought never to be put upon the general terms of any act in favour of a particular inventor, unless it be inevitable. § 560. The next power of congress is, "to consti"tute tribunals inferior to the Supreme Court." This clause properly belongs to the third article of the con |