Tea commonly took place in the best parlor, which explains why the Latimer house has nine Windsor chairs and one sofa in this room. It was common of this time period to have the first room off the entry to be the designated area for hosting such an event. At informal teas guests could sit and stand as they pleased. The Latimers would serve their tea by the fireplace as soon as it started to get cold out. The nine chairs make for easy moving and arranging of furniture. A classic seating arrangement was a semi-circle of chairs when seeing guests and against the wall when not in use.
Tea Boards, Tea Drinking in the 18th-Century America:
It's Etiquette and Equipage, Smithsonian Institution, 1961