At this time, I know that Alexander Whittle was born in about 1818, to parents Alexander and Margaret (Mansley) Whittle, in Lancashire, perhaps near Bolton. Is there a birth or christening record for him?
Back into the FamilySearch Beta English Births and Christenings, 1538-1975 Collection (with over 65 million entries) and found this record:
Alexander Whittle was born or christened on 4 January 1818 in Chorley in Lancashire. Chorley is very close to Bolton. This certainly appears to be him - he's in the right place at the right time with the right parents names (although it doesn't list his mother's maiden name).
I found at least ten other children baptized in Chorley in the 1798-1818 time frame to Alexander and Margaret Whittle. Is there a marriage record for Alexander Whittle and Margaret Mansley? The English Marriages, 1538-1973 collection (over 18 million entries) on FamilySearch Beta has this entry:
So Alexander Whittle and Margaret Mansley married on 4 July 1797 in Chorley in Lancashire. So far, everything seems to hand together here. Can I go back one more generation?
The marriage record doesn't provide an age for Alexander and Margaret, but a reasonable guess is to search the English Births and Christenings, 1538-1975 Collection for Alexander's birth in the 1565 to 1575 time frame. Here is the screen with the 5 matches for this search:
I learned today that if you click on the little down arrow to the right of the list of matches that you can see the index summary of the record without clicking on the person's name. This is a fantastic shortcut, if it doesn't hide important information. I clicked on Alexander Whittle's name in the screen above and saw: