1974 computer printout lists serial nos, of???

Susan8,578

A resource I opened for birth records is a printout done in 1974 of Births and Christenings in Weston MA from 1708-1849. Each listing has a serial number next to it, but there isn't an explanation in the doc of what they are. I was hoping to find info about the source of data, and wondered if the serial number would lead me to that.

Cover page:

Sample entry:

MaureenE123

@Susan8,578

The 2nd image refers to a batch number.

Using that batch number in the Records Search https://www.familysearch.org/en/search/ I get https://www.familysearch.org/en/search/record/results?q.batchNumber=C50158-1 and looking at the first record, I see "Massachusetts, Births and Christenings, 1639-1915", database, Family Search

Going back to the Records Search and Searching in Find a Collection, I get that database is https://www.familysearch.org/en/search/collection/1675197 with an associated FamilySearch Wiki page https://www.familysearch.org/en/wiki/Massachusetts,_Births_and_Christenings_-_FamilySearch_Historical_Records

I don't know what the serial number reference are in the document image, but you should be able to find all the records in the collection just mentioned.

Susan8,578

Thank you!