The grounds of Kensington House are spacious and well adapted to playing of noble game of cricket, base, trap-ball, quoits and other amusements; and all apparatus necessary for above games will be furnished to clubs and parties.1In June 1821, an ad ran in some New York papers announcing that Niblo has taken superb mansion formerly known as Mount Vernon, which he has furnished in a handsome style for reception of boarders and visitors.2 The mansion, now open as Kensington House, accommodated dinners and tea parties and clubs ... and, notably, ballplaying as noted above.This mention of ballplaying is, however, deceptive: seemingly simple and straightforward, yet pregnant with implications about who was playing early baseball and on what occasions.Early baseball played by adults presents problem of when they had opportunity. Accounts typically place it on special communal occasions such as barn raisings or annual holidays. There is little doubt but that these account for most adult play, but advertisement for Kensington House shows another opportunity: at resorts.Kensington House was situated on what had once been estate of Colonel William Stephens Smith, son-in-law of President John Adams. It was located on Manhattan about two hundred yards from East River. The site is now 60th Street, near west end of Queensboro Bridge. The former carriage house of estate survives on 61st Street as Mount Vernon Hotel Museum & Garden. The subject of advertisement seems to have been estate mansion, which burnt down in 1826.3In 1821 this was a country retreat several miles north of edge of development. The mansion was set up as a resort for day trips. The advertisement suggested a ride up Third Avenue, but it was also accessible by boat. The proprietor also arranged a coach holding up to 14 passengers at 25 cents each to make trip twice daily from Pine Street, in what is now Wall Street financial district.4The resort was intended for moneyed classes, promising that dinner and tea parties, clubs and societies, can be furnished with all delicacies of season, at a short notice, with private rooms fitted up for select family and friendly parties. Completing parties were Wines and Liquors ... of choicest quality.This advertisement is of interest to baseball history because of promise of spacious grounds suitable for various games and provision of necessary equipment. But was baseball one of these games? The actual reference is to the noble game of cricket, base, trap-ball, quoits and other amusements. Early citations of sometimes mean baseball, but not always. They can also refer to prisoner's base, a form of tag unrelated to baseball. In this case, however, we can be confident that does indeed refer to baseball. It is sandwiched between two other games involving a bat and ball: a natural fit for baseball, but odd for prisoner's base. More definitively, prisoner's base does not require any equipment, which would make promise of its provision superfluous.5We can also be confident that this was not merely a diversion for visitors' children. Cricket and quoits (a form of ring toss) were well established adult activities. John Marshall, Chief Justice of United States at time, is known to have been an active quoits player. It would be odd to place a children's diversion in such a list.This item is strikingly similar to Protoball 1822.3, which is an advertisement in Philadelphia's Saturday Evening Post for a similar establishment on west bank of Schuylkill River, in what is now west Philadelphia. This too was a resort destination situated in countryside within day-trip distance of city. Along with promise of good food and drink, it offered accommodation for quoit and cricket and other ball clubs. Clearly Kensington House was not an isolated phenomenon. …