The two chief causes of the badness of indexes are found—
1. In the original composition.
2. In the bad arrangement.
Of the first cause little need be said. The chief fault is due to the incompetence of the indexer, shown by his use of trivial references, his neglect of what should be indexed, his introduction of what might well be left out, his bad analysis, and his bad headings.
The second cause is still more important, because a competent indexer may prepare his materials well, and keep clear of all the faults noticed above, and yet spoil his work by neglect of a proper system of arrangement.
The chief faults under this second division consist of—
1. Want of complete alphabetisation.
2. Classification within the alphabet.
3. Variety of alphabets.
These are all considerable faults, and will therefore bear being enlarged upon.
1. The want of complete alphabetisation is a great evil, but it was very general at one time. In some old indexes references are arranged under the first letter only. In the index to a large and valuable map of England, published at the beginning of this century, the names of places are not arranged further than the third letter, and this naturally gives great trouble to the consulter. In order to save himself, the compiler has given others a considerably greater amount of trouble. In arranging entries in alphabetical order it is necessary to sort them to the most minute difference of spelling. The alphabetical arrangement, however, has its difficulties, which must be overcome; for instance, it looks awkward when the plural comes before the singular, and the adjective before the substantive from which it is formed, as "naval" and "navies" before "navy." In such cases it will be necessary to make a heading such as "Navy," which will include the plural and the adjective.
The vowel I should be kept distinct from the consonant J, and the vowel U from the consonant V.
More blunders have probably been made by the confusing of u and n in old books than from any other cause. These letters are identical in early manuscripts, and consequently the modern copyist has to decide which letter to choose, and sometimes he blunders.