premise: Seated on the <mask> were Amos C. Barstow , ex-mayor of Providence and a wealthy Republican stove manufacturer ; Thomas Davis , an uncompromising Garrisonian ; the Reverend Augustus Woodbury , a Unitarian minister ; the Reverend George T. Day , a Free-Will Baptist ; Daniel w. Vaughan , and William H. H. Clements .
hypothesis: the proper context for <mask> here should be a raised horizontal surface