Soundex filing system, alphabetic for the first letter of surname and numeric thereunder as indicated by divider cards, keeps together names of the same and similar sounds but of variant spellings.

To search for a particular name, you must first work out the code number for the surname of the individual. No number is assigned to the first letter of the surname. If the name is Kuhne, for example, the index card will be in the "K" segment of the index. The code number for Kuhne, worked out according to the system below, is 500.

Every Soundex number must be a 3-digit number. A name yielding no code numbers, as Lee, would thus be L-000; one yielding only one code number would have two zeros added, as Kuhne, coded as K-500; and one yielding two code numbers would have one zero added, as Ebell, coded as E-140. Not more than three digits are used, so Ebelson would be coded as E-142, not E- 1425.

When two key letters or equivalents appear together, or one key letter immediately follows or precedes an equivalent, the two are coded as one letter, by a single number, as follows: Kelly, coded as K-400; Buerck, coded as B-620, Lloyd, coded as L-300; and Schaefer, coded as S-160.

If several surnames have the same code, the cards for them are arranged alphabetically by given name. There are divider cards showing most code numbers, but not all. For instance, one divider may be numbered 350 and the next one 400. Between the two divider cards there may be names coded 353, 350, 360, 365, and 355, but instead of being in numerical order they are interfiled alphabetically by given name.

Such prefixes to surnames as "van," "Von," "Di," "de," "le," "Di," "D'," "dela," or "du" are sometimes disregarded in alphabetizing and in coding.

The following names are examples of Soundex coding and are given only as illustrations.

Researchers using the Soundex system to locate religious nuns or persons with Native American or Asian names should be aware of the way such names were coded. Variations in coding differed from the normal coding system.

Phonetically spelled Asian and Native American names were sometimes coded as if one continuous name, or, if a distinguishable surname was given, the names were coded in the normal manner. For example, the American Indian name Shinka-Wa-Sa may have been coded as "Shinka" (S-520) or "Sa" (S-000). Researchers should investigate the various possibilities of coding such names.

Religious nun names were coded as if "Sister" were the surname, and they appear in the Soundex indexes under the code "S-236." Within the code S-236, the names may not be in alphabetical order.