4 ON THE EVOLUTION OF LANGUAGE. 
c. By agglutination, in which case one or more of the elements enter- 
ing into combination to form the new word is somewhat changed—the 
elements are fused together. Yet this modification is not so great as 
to essentially obscure the primitive words, as in truthful, where we easily 
recognize the original words truth and full; and holiday, in which holy 
and day are recognized. f 
d. By inflection. Here one or more of the elements entering into the 
compound has been so changed that it can scarcely be recognized. 
There is a constant tendency to economy in speech by which words are 
gradually shortened as they are spoken by generation after generation. 
In those words which are combinations of others there are certain ele- 
ments that wear out more rapidly than others. Where some particular 
word is combined with many other different words the tendency to 
modify by wear this oft-used element is great. This is more especially 
the case where the combined word is used in certain categories of com- 
binations, as where particular words are used to denote tense in the 
verb; thus, did may be used in combination with a verb to denote past 
time until it is worn down to the sound of d. The same wear occurs 
where particular words are used to form cases in nouns, and a variety of 
illustrations might be given. These categories constitute conjugations 
and declensions, and for convenience such combinations may be called 
paradigmatic. Then the oft-repeated elements of paradigmatic combina- 
tions are apt to become excessively worn and modified, so that the primi- 
tive words or themes to which they are attached seem to be but slightly 
changed by the addition. Under these circumstances combination is 
called inflection. 
As a morphologic process, no well-defined plane of demarkation be- 
tween these four methods of combination can be drawn, as one runs into 
another ; but, in general, words may be said to be juxtaposed when two 
words being placed together the combination performs the function of 
a new word, while in form the two words remain separate. 
Words may be said to be compound when two or more words are com- 
bined to form one, no change being made in either. Words may be said 
to be agglutinated when the elementary words are changed but slightly, 
i. é., only to the extent that their original forms are not greatly ob- 
secured; and words may be said to be inflected when in the combination 
the oft-repeated element or formative part has been so changed that its 
origin is obscured. These inflections are used chiefly in the paradig- 
mnatic combinations. 
In the preceding statement it has been assumed that there can be rec- 
ognized, in these combinations of inflection, a theme or root, as it is 
sometimes called, and a formative element. The formative element is 
used with a great many different words to define or qualify them; that 
is, to indicate mode, tense, number, person, gender, etc., of verbs, nouns, 
and other parts of speech. 
When in a language juxtaposition is the chief method of combination, 
