Access 97 Query

I have a query with 2 fields. One is a Slip number, which is a number that should increment by one for each record.

Is there anyway to have access tell from one record to the next if the number goes up by more than one? ie. a Slip has been skipped.

These numbers are hand entered, because they relate to hard copies. It cannot be auto incrememnt.

Thx, Loyd