The following Memoir, therefore, must claim the indulgence due to a first essay in a new and difficult subject. No one can be more sensible than the writer of its many imperfections;—of the probable omission of names which should have been recorded;—of the undue prominence of others with inferior pretensions; and perhaps of still more serious inaccuracies of a different kind. It is only offered in the absence of something better and more complete; and with the hope of directing to what is certainly a curious and interesting subject, the attention of others who enjoy more leisure and opportunity for its investigation. * * * * * The diversity of languages which prevails among the various branches of the human family, has proved, almost equally with their local dispersion, a barrier to that free intercommunion which is one of the main instruments of civilization. “The confusion of tongues, the first great judgment of God upon the ambition of man,” says Bacon, in the Introductory Book of his “Advancement of Learning,” “hath chiefly imbarred the open trade and intercourse of learning and knowledge.”[1] Perhaps it would be more correct to say that these two great impediments to intercourse have mutually assisted each other. The divergency of languages seems to keep pace with the dispersion of the population. Adelung lays it down as the result of the most careful philological investigations, that where the difficulties of intercourse are such as existed among the ancients and as still prevail among the less civilized populations, no language can maintain itself unchanged over a space of more than one hundred and fifty thousand square miles.[2] It might naturally be expected, therefore, that one of the earliest efforts of the human intellect would have been directed towards the removal of this barrier, and that one of the first sciences to invite the attention of men would have been the knowledge of languages. Few sciences, nevertheless, were more neglected by the ancients.