Skip,
I realize that, but the table I am linked to is storing the date as a text field, not as a date field. Why, I do not know. Instead of using a Date/Time field, they use a text field for the date and another one for the time. Each record has several times recorded, and for each one they use a date and time field in text format.
I am using DateValue, and TimeValue and combining the two to get back to a regular Date/Time format in my query. Then I am subtracting the earlier from the later, to come up with a time interval.