The above letters had been thrown into the waste paper by some careless postmaster or clerks, and sold at two and a half cents per pound; and some other postmaster or clerks have been under suspicion of committing a depredation upon those letters; and had this girl been dishonest they might never have been able to convince the parties interested of their innocence. This is inexcusable carelessness; and postmasters who read this article should see that they or their clerks are not caught in this way. _SEALING-WAX._ Under no circumstances use sealing-wax for postal purposes. Wax should only be used for letters or documents when a person is anxious to _display his seal or coat of arms_, or where it may be required for a legal purpose, and only then when they are more effectually secured. The practice of sealing letters passing more particularly through warm climates with wax is attended with much inconvenience, and frequently with serious injury, not only to the letters so sealed, but to the other letters in the mail, from the melting of the wax and adhesion of the letters to each other. The public are, therefore, recommended in all such cases to use either wafers or gum, and to advise their correspondents in the countries referred to to do the same. English newspapers—indeed, nearly all European printed matter—come to us sealed with _bad wax_; and if many of them were not secured by thread, few would ever reach the parties to whom they are addressed. _COMPLAINTS ABOUT MISTAKES._ When complaint is made of letters or newspapers lost, miscarried, or delayed, to furnish information as precise as possible regarding all the facts of the case, and to enclose whatever documents may throw light upon it. The day and hour at which the letter or newspaper was posted, as well as the office at which and the person by whom this was done, should always be stated, and, when possible, the cover or wrapper, in an entire state, should be sent, in order that the place of delay may be ascertained by an examination of the stamps. Cases frequently occur in which complaint is made against the post-office and redress expected, although little or no means of tracing the error and of guarding against a repetition of it is supplied by those who alone are able to do so. _A LAW CASE._ In 1806 a case was tried in the District Court of Maryland, “United States _vs._ Barney,” which we deem essential to the nature of our work. “WINCHESTER, J.—The indictment in this case, which charges the defendant with having wilfully obstructed the passage of the public mail at Susquehanna River, is founded on the act of Congress of March, 1799. “The defendant sets up as a defence and justification of this obstruction of the mail that he had fed the horses employed in carrying the mail for a considerable time, and that a sum of money was due to him for food furnished at and before the time of their arrest and detention.