The batch numbers used in the International Genealogical Index (IGI), as well as in the 72 million entries at <pilot.familysearch.org>, can make plowing through the piles of Mexican records muy simple.
A batch search lets you jump from the record for one ancestor to other record extracts entered at the same time from the same parish or town. Once you’ve done a successful IGI search—say, you’ve found your ancestor Martin Hernandes, christened June 15, 1834, in Huejutla De Reyes, Hidalgo—just click on the batch number (C612612) in the lower left corner of the screen. That automatically brings up a new IGI search on the batch number. Now you can fine-tune your criteria or just click Search to see all individuals from the batch. (If you’ve found an ancestor at <pilot.familysearch.org>, just copy the batch number and paste it into an IGI search.)
Volunteers at Mexico IGI Batch Numbers have indexed 3,550 batch numbers for 32 states. If you know your ancestral town, click on the state and scroll through the list of towns to see the batch numbers for that town. Baptisms from 1833 to 1839 at San Nicolas de Tolentino in Actopan, Hidalgo, for example, are under batch number C612926, which you can then search for in IGI. A similar indexing project is underway (in Spanish only) at <www.hispagen.org/america/mexico.asp>.
For more on searching with IGI batch numbers, see <wiki.familysearch.org/enIGI_Batch_Numbers_for_Latin_American_Countries> and <hispanicgenealogy.blogspot.com/2007/07/igi-on-familysearchorg.html>.
From the January 2009 Family Tree Magazine