The U.S. Federal Census, taken every ten years beginning in 1790, is a reference where genealogists spend lots of time. We spend hours poring through reels of microfilm seeking verification that our ancestors were in a specific place at a given point in time.

Census indexes, when available, are invaluable tools. They help us quickly locate individuals in the voluminous census documents. Printed index books list people by surname and then first names. But there's another index that is often overlooked: the Soundex system. And that's the topic of this week's "Along Those Lines ..." column.

The Soundex system was developed in the 1930s by the WPA for the Social Security Administration. The SSA needed a way to identify people who would be eligible to receive old-age benefits, specifically those people who were born in the 1870s and later. While the SSA began its identification process using the 1880 census documents, there were so many spelling errors that another means of locating records for potential beneficiaries had to be developed.

The Soundex system allowed for the use of sounds in a surname to be used to classify and index heads of household in the census records. All spellings of Smith, Smithe, Smyth, Smythe, and other variations that sound alike will be indexed together.

Households from the 1880 census with children aged 10 and under were Soundexed. (There are exceptions, additions and omissions but that was the intent.) The 1890 census was destroyed by fire. Soundex was also used in 1900, 1910 and 1920 for some states. Another, similar code called Miracode was added for use in the 1910 census. In the 1910 census, there are only 21 states' census records which are Soundexed or Miracoded.

Today, the Soundex records are available on microfilm and may be just the tool you need to locate the census record for your ancestors during the census years mentioned above. On a recent visit to a Family History Center, a friend located the Soundex record of his great-grandparents and their children. He had been searching the 1880 census records of Edgefield County, SC, for a long time without success. The Soundex identified the place of residence as being in Aiken County, SC. This was a major breakthrough!

The Soundex system is based on surnames. The Soundex code consists of a letter and three numeric digits. To code a surname using the Soundex system, follow these simple instructions.

The letter at the beginning of the Soundex is always the first letter of the surname. Next, you proceed in sequence through the surname and assign a number to the next three consonants in the surname. You ignore the vowels and any more than three consonants. The numbers you assign are as follows:

1 B, P, F, V
2 C, S, K, G, J, Q, X, Z
3 D, T
4 L
5 M, N
6 R

My surname MORGAN, for example, would become Soundex code M625. The surname ROBERTSON would become R163. No more than three numeric codes are used. (Note that the S and N in ROBERTSON were ignored.)

What if there aren't enough consonants to make three numerics? Simple! You use a zero. For example, the surname DEAN would become D500. General Robert E. LEE would have had a surname of L000.

If the surname has a prefix, such as De, De la, La, Van, Von, the Soundex code may or may not have been coded using those letters.

If two letters appear together that are the same (as with the double t in PATTERSON) or have the equivalent value (as with the "ck" in PACKER), only the first letter is coded. (PATTERSON would become Soundex code P362 and PACKER would become P260.)

WPA workers worked through the census records for an entire state and transcribed information onto the Soundex cards. Soundex codes were then assigned and the cards were sorted. The sortation was done by Soundex number and then alphabetically by head of household's first name. The resultant file of Soundex cards was later microfilmed.

Therefore, you should expect to work with one state's Soundex microfilm for a given Soundex code or several codes on a roll of microfilm. You will see different surnames as you proceed through the records. For instance, you might see the Smith, Smithe, Smyth, Smythe, and other variations in the same Soundex code group, alphabetized by surname.

Please note that the 1880 Soundex may be incomplete. Soundex cards were not always made up for families where there were no children under the age of ten. Other portions may be missing as well.

Content of the Soundex vary based on the year, just as the questions varied from census to census. 1920 census Soundex cards contain:

Soundex Code
State
Surname, First Middle (Head of household)
Volume # (of the census)
Enumeration District (Helps you locate the right portion of the census)
Sheet (Page number of the census)
Line (Line number on which head of household's name appears)
Color (Head of household)
Sex (Head of household)
Age (Head of household)
Birthplace (Head of household)
Citizenship (Head of household)
City
Street
House number

Other Members of the Family
Surname, First Middle
Relationship (W = wife; S = son; D=daughter; A = aunt; B = brother;
Si = sister; F = father -- other codes exist)
Age
Birthplace

The Soundex can help you narrow your search within a state down to a smaller area and, with later years, even to an enumeration district, a town, a street and a house number. If you're unsure of the state in which your ancestor lived, you can start with the one in which you "think" he or she lived and work through other possible states.

If you're searching for the location of an orphan, it's possible that he or she is living with a relative. The use of Soundex records, and the relationship codes, may help you identify the person's identity and distinguish him or her from others.

Soundex records open another avenue of genealogy research for you. And while they may contain errors, may omit some households, and may contain spelling errors, they are nevertheless good secondary records. Don't overlook them.

If your genealogy library doesn't have Soundex microfilm, try the nearest LDS Family History Center (FHC). Otherwise, ask your librarian or the elder at the FHC to order the Soundex microfilm for your use.

For more information about Soundex, please check the Genealogy Records Service Web site at http://www.genrecords.com/forms.htm. They have reference materials about the Soundex, including the list of Soundex relationship abbreviations.

In the meantime,