No librarian can know too much, since his work brings him into relation with the boundless domain of human knowledge. He should not be a specialist in science (except in the one science of bibliography) but must be content with knowing a little about a great many things, rather than knowing everything about one thing. Much converse with books must fill him with a sense of his own ignorance. The more he comes to know, the wider will open before him the illimitable realm of what is yet to be known. In the lowest deep which research the most profound can reach, there is a lower deep still unattained--perhaps, even, unattainable. But the fact that he cannot by any possibility master all human knowledge should not deter the student from making ever advancing inroads upon that domain. The vast extent of the world of books only emphasizes the need of making a wise selection from the mass. We are brought inevitably back to that precept by every excursion that we make into whatever field of literature. The librarian should possess, besides a wide acquaintance with books, a faculty of administration, and this rests upon careful business habits. He should have a system in all the library work. Every assistant should have a prescribed task, and be required to learn and to practice all the methods peculiar to library economy, including the economy of time. Each day's business should be so organized as to show an advance at the end. The library must of course have rules, and every rule should be so simple and so reasonable that it will commend itself to every considerate reader or library assistant. All questions of doubt or dispute as to the observance of any regulation, should be decided at once, courteously but firmly, and in a few words. Nothing can be more unseemly than a wrangle in a public library over some rule or its application, disturbing readers who are entitled to silence, and consuming time that should be given to the service of the public. When Thomas Carlyle, one of the great scholars of modern times, testified in 1848 before a Parliamentary Commission upon the British Museum Library, he thus spoke of the qualifications of a librarian: "All must depend upon the kind of management you get within the library itself. You must get a good pilot to steer the ship, or you will never get into the harbor. You must have a man to direct who knows well what the duty is that he has to do, and who is determined to go through that, in spite of all clamor raised against him; and who is not anxious to obtain approbation, but is satisfied that he will obtain it by and by, provided he acts ingenuously and faithfully."