The May 22 edition has an article abut the ceremony at Memorial Plaza. Among other things it says that there will be a 21-gun salute by the Whiting Field Color Guard. I suspect what is meant is there will be three rifle volleys fired by a squad of riflemen from Whiting Field.
A 21-gun salute is usually fired by cannon or ships guns to honor presidents, kings or other countries for example. There maybe lesser number of guns for lesser lights.
Paul Johnson
Milton
This article originally appeared on Santa Rosa Press Gazette: Seven guns, three times