tours of word-curves are necessarily due to any personal peculiarities in the respective authors.
The average word-length may be reasonably assumed to depend upon other factors besides the author's word-sense, as the form of composition, the subject matter, etc. A man's gait differs according as he is walking for pleasure or on business, alone or in the company of others, on a long journey or to escape from danger. Similarly the average word-length of the language current in the market place, the street or the drawing-room differs from that employed on the rostrum, in learned discourse or in polite conversation, even though used by the same person. Why should not this difference manifest itself in the written utterances of an author?
Dr. Mendenhall, by an enormous expenditure of labor, attempts to prove his second assumption. How? By taking for granted the converse of the very proposition which he wishes to establish. He actually constructs the word-curves for Mill, Jonson, Dickens, Bacon, Shakespeare and finding that they differ in contour, attributes these differences to personal peculiarities of the respective authors. Not once seems the question to have been raised, much less answered, whether these differences are not due wholly or in part to other determining conditions, such as the form of composition or other accidents.
Now not only can it be shown that the form of composition, at least, is a modifying factor of the word-curve and average word-length, but it appears, indeed, to be the predominating factor, overshadowing all others. Works agreeing in form of composition, though written by different authors, will be found to yield curves more nearly in agreement than different works of widely divergent forms of composition by the same author. Whether or not the author-component in the word-curve can be separated from the others is unknown; certain it is that nothing of the kind has as yet been attempted. With our present knowledge concerning word-curves, conclusions regarding the authorship of spurious or disputed writings based upon a comparison of the word-curves of works differing either in the form of composition or in other essential respects must be considered worthless.
It is not difficult to predict in a general way in what respects word-curves of different types of composition will differ. In the vernacular of a language, so nearly devoid of inflection as our English, three-and four-letter words will naturally predominate. The development of oral speech, following the path of least resistance, will naturally be from the simple to the complex. Combinations of five, six or more letters, representing as many elements of sound, will not generally be resorted to so long as there are abundant simpler combinations, consistent with the possibilities of vocal articulation, to draw from. Now while the possible combinations of two and three letters into words is