are usually named and defined with reference to the use of words in sentences; and, as the same word not unfrequently stands for several different parts of speech, the learner should be early taught to make for himself the proper application of the foregoing distribution, without recurrence to a dictionary, and without aid from his teacher.  He who is endeavouring to acquaint himself with the grammar of a language which he can already read and understand, is placed in circumstances very different from those which attend the school-boy who is just beginning to construe some sentences of a foreign tongue.  A frequent use of the dictionary may facilitate the progress of the one, while it delays that of the other.  English grammar, it is hoped, may be learned directly from this book alone, with better success than can be expected when the attention of the learner is divided among several or many different works.

OBS. 3.—­Dr. James P. Wilson, in speaking of the classification of words, observes, “The names of the distributive parts should either express, distinctly, the influence, which each class produces on sentences; or some other characteristic trait, by which the respective species of words may be distinguished, without danger of confusion.  It is at least probable, that no distribution, sufficiently minute, can ever be made, of the parts of speech, which shall be wholly free from all objection.  Hasty innovations, therefore, and crude conjectures, should not be permitted to disturb that course of grammatical instruction, which has been advancing in melioration, by the unremitting labours of thousands, through a series of ages.”—­Wilson’s Essay on Gram., p. 66.  Again:  “The number of the parts of speech may be reduced, or enlarged, at pleasure; and the rules of syntax may be accommodated to such new arrangement.  The best grammarians find it difficult, in practice, to distinguish, in some instances, adverbs, prepositions, and conjunctions; yet their effects are generally distinct.  This inconvenience should be submitted to, since a less comprehensive distribution would be very unfavourable to a rational investigation of the meaning of English sentences.”—­Ib., p. 68.  Again:  “As and so have been also deemed substitutes, and resolved into other words.  But if all abbreviations are to be restored to their primitive parts of speech, there will be a general revolution in the present systems of grammar; and the various improvements, which have sprung from convenience, or necessity, and been sanctioned by the usage of ancient times, must be retrenched, and anarchy in letters universally prevail.”—­Ib., p. 114.