Add-on to the higher officiers:
In the regiment there were more majors or sometimes lt.colonels or colonels (like 'colonel en second' in the French Army in 1809).
There were difference between the majors. The captain was promoted to an occupied a second major position. At the next promotion he became first major and thereafter lt.colonel. Sometimes there were third major an 'major overnumber'. A third major had to train the green soldiers home or commanded the reserve squadron/division at field.