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Q. What’s the “lost rule” of Soundex, and how does it affect the codes for my ancestral surnames?
A. Soundex is an indexing system that groups surnames together by codes based on their consonant sounds. Each code begins with the first letter of the name, followed by three numbers, representing consonants in the name (see the Soundex key). To form the three-digit code, first strike out vowels and y. Most of us were taught to strike out h and w and treat them as vowels — but some names need the “lost rule” or the “H and W rule.”
These examples show the use of the lost rule on 1900 census Soundex cards:
? Ashcroft: A261 (coding A-sc-r-f), not A226 (using A-s-c-r)
? Mitschke: M320 (coding M-t-sck-0), not M322 (using M-t-sc-k)
? Rothdeutsch: R332 (coding R-td-t-sc), not R333 (using R-t-d-t)
? Schsekoweske: S220 (coding Scs-k-sk-0), not S222 (using Sc-s-k-sk)
? Sochse or Sachse: S200 (coding S-cs-0-0), not S220 (using S-c-s-0)
? Smithton: S535 (coding S-m-tt-n), not S533 (using S-m-t-t)
If you don’t find your name under the code using the lost rule, try the other possibility in case your name was Soundexed with the h or w treated the same as vowels.
Some online Soundex code generators use the lost rule and others don’t. If you learn the system, you can evaluate the codes provided on Web sites yourself. Converters that use the lost rule include:
? Soundex Converter by RootsWeb <resources.rootsweb.ancestry.com/ cgi-bin/soundexconverter>
? How to Research the 1930 Census Microfilm <1930census.archives.gov/beginsearch.asp> (select a state Soundexed in 1930)
? Yet Another Soundex Converter <www.bradandkathy.com/cgi-bin/yasc.cgi>
Note that when you choose the Soundex search option on various genealogy Web sites, your results may not adhere to the lost rule, or even original Soundex codes. The searches pick up other names with similar sounds, including, but not limited to, ones with the same Soundex code.