use are the same as those in use in England. The English brass Troy pound is the legal Troy pound at the mints, while the Imperial avoirdupois pound and the wine gallon rest upon usage. Congress has authorized the use of the metric system of weights and measures, but has not made it compulsory.

387. The Postal Service.-Congress has created the vast postal system of the country, the cost of which in the year 1894 was more than $84,000,000. The mails are carried by contractors. Postmasters paid $1,000 or more a year are appointed by the President for a term of four years; all others by the Postmaster-General at his pleasure. A great majority of the postmasters do not receive regular salaries, but a percentage on the income of their offices. Towns having gross post-office receipts of $10,000 or more have free mail delivery by letter-carriers. In towns of 4,000 inhabitants or more letters bearing a special 10-cent stamp are delivered by a special carrier immediately on their receipt. Letters may also be registered to secure their greater safety in delivery on payment of a 10-cent fee. Money orders are also sold by certain post-offices called money-order offices, which to a limited extent take the place of money in the transaction of business.

388. Rates of Postage.-There are four classes of domestic mail matter bearing different rates of postage. All postage must be pre-paid in the form of stamps.

1. Letters, postal cards, and other written matter, and all packages that are closed to inspection. Save on postal cards and drop letters mailed at non-delivery offices, the rate is two cents an ounce or fraction of an

ounce.

2. Periodicals, magazines, etc. The rate on matter of this class when sent from a registered publishing

office, or a news agency, is one cent a pound; when sent otherwise, it is one cent for every four ounces.

3. Books, authors' copy accompanying proof-sheets, etc., are charged one cent for two ounces or fraction of the same.

4. Merchandise limited to 4-pound packages is charged one cent an ounce.

389. Copyrights and Patent Rights. For promoting science and the arts, Congress provides that authors may copyright their works and inventors patent their inventions for limited times. The author of a book, chart, engraving, etc., by means of a copyright, enjoys the sole liberty of printing, publishing, and selling the same for twenty-eight years, and on the expiration of this time he, if living, or his wife or his children if he be dead, may have the right continued fourteen years longer. An inventor also, by means of letters patent, enjoys the exclusive right to manufacture and sell his invention for seventeen years, and on the expiration of that period the Commissioner of Patents may extend the right, if he thinks the invention sufficiently meritorious. Copyrights are obtained from the head of the Library of Congress, patent rights from the head of the Patent Office, both at Washington. The cost of a copyright is one dollar and two copies of the book or other work. The cost of a patent right is $35.00. Every article that is copyrighted or patented must be appropriately marked.

390. Piracies and Felonies.-Congress defines the punishment of piracies and felonies on the high seas, and offenses against the Law of Nations. In a general sense piracy is robbery or forcible depredation of property on the seas, but Congress has by law declared some other acts, as engaging in the slave trade, to be piracy.

Felonies, strictly speaking, are crimes punishable by death. The Law of Nations is a body of rules and regulations that civilized nations observe in their intercourse one with another. The high seas are the main sea or ocean, which the law of nations limits by a line drawn arbitrarily at one marine league, or three miles, from the shore.

391. Powers of Congress in Relation to War.— Congress has the power to declare war, which in monarchical countries is lodged in the Crown. It raises and supports armies. It provides a navy. It makes rules for the government of the army and navy. It provides for calling out the militia of the States to execute the laws of the Union, to suppress insurrection, and repel invasion. It provides for organizing, arming, and disciplining the militia, and for the government of such of them as may be called into the service of the United States; but the States have authority to appoint the officers and to train the militia according to the discipline that Congress has prescribed. These powers are very far-reaching. Acting under the laws of Congress, President Lincoln, in the course of the Civil War, called into the service of the Union fully 3,000,000 men. A navy counting hundreds of vessels was also built. At present the army consists of 25,000 officers and enlisted men. The navy consists of 38 vessels in commission for sea service. At present the highest title in the army is General, the highest in the navy Rear-Admiral. The soldiers of the United States are divided into the

regular troops and the militia. The former are in constant service; the latter are the citizen soldiery enrolled and organized for discipline and called into service only in emergencies. In the fullest sense of the word, the militia are the able-bodied male citizens of the States

between the ages of eighteen and forty-five. The President cannot call them into active service for a longer period than nine months in any one year. In service, they are paid the same as the regular troops.

392. The Federal District.-Previous to 1789 the United States had no fixed seat of government, and Congress sat at several different places. The resulting evils led the Convention of 1787 to authorize Congress to exer cise an exclusive legislation over a district, not more than ten miles square, that particular States might cede and Congress might accept for a capital. The cession of Maryland and the acceptance of Congress made the District of Columbia the Federal District, and an act of Congress made Washington the Capital of the Union. The various branches of the Government were established there in 1800. The District is now governed by a board of three commissioners, two appointed by the President and Senate, and one an engineer of the army who is detailed by the President for that purpose. Congress pays one-half the cost of government, the people of the District the other half. Congress also has jurisdiction over places within the States that have been purchased for forts, arsenals, magazines, dock-yards, and other needful public buildings.

393. Necessary Laws. It must be borne in mind. that the government of the United States is a government of delegated powers. Still these powers are not all expressly delegated. There are powers delegated by implication, as well as powers delegated in words. Congress is expressly authorized to make all laws that are necessary for carrying into effect the powers that have been described above, and all other powers that the Constitution vests in the Government of the United States, or any department or officer of that Government.

Congress, improves harbors, erects lighthouses, builds post-offices and custom houses, and does a thousand other things that are not particularly named in the Constitution, because in its judgment they are necessary to the execution of powers that are particularly named. The power to establish post-roads and post-offices, for example, or to create courts, involves the power to build buildings suitable for these purposes. This is known as the doctrine of implied powers.

Looking over the general powers of legislation that are vested in Congress, described above, we see how necessary they are to a strong and efficient government. They are the master power, the driving force, of our whole National system. If these eighteen clauses were cut out of the Constitution, that system would be like a steamship without an engine.