This is the O'Neil Dairy building (formerly the Ames Armory) and its truck looking west on Fifth Street.  The Ames Daily Tribune's building can be seen across the street.  ca. 1940 (Farwell T. Brown Photographic Archive)

O'Neil's made premium ice cream, with butterfat content as high as 6 to 7%.  It melted in your mouth and clung to your lips.  The scoop was a way to exercise some degree of portion control when serving ice cream.  This one was used for a 5 cent ice cream cone that consisted of one scoop.