I have been very often asked for a book which will 'tell one everything.' There is no such book, and there never could be such a book. Omniscience may be a foible of men, but it is not so of books. Knowledge, as Johnson said, is of two kinds, you may know a thing yourself, and you may know where to find it.[24] Now the amount which you may actually know yourself must, at its best, be limited, but what you may know of the sources of information may, with proper training, become almost boundless. And here come the value and use of reference books—the working of one book in connexion with another—and applying your own intelligence to both. By this means we get as near to that omniscient volume which tells everything as ever we shall get, and although the single volume or work which tells everything does not exist, there is a vast number of reference books in existence, a knowledge and proper use of which is essential to every intelligent person. Necessary as I believe reference books to be, they can easily be made to be contributory to idleness, and too mechanical a use should not be made of them. Very admirable reference books come to us from America, where great industry is shown, and funds for publishing them never seem to be short. The French, too, are excellent at reference books, but the inferior way in which they are printed makes them tiresome to refer to. Larousse's Grand Dictionnaire is a miracle.

A good atlas is essential as a reference book, and maps of the locality where we live. A good map of old London is very useful in studying Pepys' Diary for instance. A good verbal dictionary is essential. Sometimes several should be in use: thus, Halliwell's Archaic Dictionary and Nares' Glossary are useful in studying Shakespeare. Richardson's Dictionary embodies all the good points of Johnson's Dictionary, and is very excellent for quotations. Poetical Concordances and Dictionaries of Quotations, both prose and poetry, are useful, though very rarely does one find the quotation required in any professed book of quotations. A good Biographical Dictionary is a joy; such is Lippincott's, an American work. A good Classical Dictionary is also necessary, and may be supplemented by Smith's Dictionary of Greek and Roman Biography. It would be interesting to see how far it would be possible to collect an ideal reference library, and this, I think, has never been carefully done. It must be borne in mind that reference books are not all books arranged alphabetically (though the man who first wrote an alphabeted book should be Canonised). Reference books consist of such works as Rawlinson's Historical Works, Wilkinson's History of the Ancient Egyptians, and Fergusson's History of Architecture. All such books are reference books, and many thousands more. I think it will be found a good plan in the library to keep reference books (viz., those which are likely to be in frequent use) in a separate case—perhaps a revolving case—and in no library should this section be neglected. Mr. Walter Wren, the well-known coach, once lectured on 'What is Education?' and in his lecture he made the following remarks:—

'I think the first thing that made me a teacher was my noticing, when a boy, how men and women read books and papers, and knew no more about them when they had read them than they did before..... Lots of people seem to know nothing, and to want to know nothing; at any rate, they never show any wish to learn anything. I was once in a room where not one person could say where Droitwich was; once, at a dinner of fourteen, where only one besides myself knew in what county Salisbury was. I have asked, I believe, over a hundred times where Stilton is, and have been told twice—this when Stilton cheese was handed. I mention this to show the peculiar conservative mental apathy of Englishmen.'

'A reader should be familiar with the best method by which the original investigation of any topic may be carried on. When he has found it, he appreciates, perhaps for the first time, for what purpose books are for, and how to use them..... No person has any claim to be a scholar until he can conduct such an original investigation with ease and pleasure.' The foregoing was the advice of a well-known American librarian.