Adapted from the 1987 House Tour Guide (Page 487)

Starting about 1835-1840, a merchant, Jacob Mott Kirby, had been buying up land in this vicinity. Kirby was a "Captain" by virtue of his shipping activities, involving ownership of several coastwise schooners, which transported farm produce and lumber to New York City and brought back agricultural implements, dry goods, and fertilizers to Roslyn Village. By around 1873, according to the Beers, Comstock & Cline Map, Captain Kirby's name was associated with many properties in the Village.

A partial "tour" of Captain Kirby's real estate holdings, following the 1873 map, might begin at the north end of the triangle, close to the "Far Pond," on the lower half of East Broadway. From the south boundary of the Conklin property as it was in 1873, all the way down to the southern end of East Broadway, as delineated by its intersection with Main Street, the land is designated as the property of "J.M. Kirby," including, at the extreme southern end of the road, on the east side, the "J.M. Kirby Residence]." It is believed that this house may originally have been a late Federal-style dwelling, which Captain Kirby later enlarged and remodeled in the Greek Revival style. Locally referred to as "the Kirby Mansion," it featured a gable facade on East Broadway, with 4 two-story classical columns supporting a second story porch.

Captain Jacob Kirby died at the age of 75 years in 1880. His properties at Kirby's Corners were inherited by his son, the Reverend William Wallace Kirby, who was the second minister of the Roslyn Presbyterian Church. The Reverend Kirby died in 1901, leaving the property to his wife and cousin Susan Eliza Kirby, who in 1918 deeded them over to her son, Ralph Kirby. Ralph Kirby made his home in the "Mansion" with his mother. His younger brother, New York University trained engineer Isaac Henry Kirby, lived with his wife Susan Ludlum in the Van Nostrand-Starkins House, as had the Reverend Wallace Kirby before his father's death.

Ralph Kirby left the Kirby properties in their entirety to Katherine Virginia Roe Applegate, a cousin of his who had grown up in Huntington and had later come to Roslyn to make a home for herself and her young son Harold Ward Applegate, Jr., with Ralph Kirby and his mother. They all lived in "the Kirby Mansion." It has been told to the writer (ELW) that Ralph Kirby was an old man when Virginia Applegate, who was about thirty years younger than him, came to live in his house; so this may have occurred shortly after the birth of her son. Just a few years after the death of Ralph Kirby, Virginia Applegate executed the first of a series of sales of Kirby land, resulting in essentially the first break-up of the property since it had been acquired nearly 100 years earlier by Captain Jacob Mott Kirby.

The property on which the Van Nostrand-Starkins House and the Captain Jacob M. Kirby Tenant House stood adjacent to each other on the west side of Main Street was sold to a single buyer in 1937, although it was subsequently sub-divided; later the Chalet Apartments were constructed on the southern portion of the property. Four years later, in 1941, the Kirby "Mansion" was sold and partly demolished, but the handsome Greek Revival portico end which Captain Kirby had added facing East Broadway was removed for re-installation in the Cornelius Vanderbilt Whitney Residence in Wheatley Hills; the Garden Apartments now occupy the site of the former "Mansion," and the Whitney home has now become the Old Westbury Country Club.

The Kirby Mansion on the southern side of East Broadway at the intersection of Main Street (circa 1880).

In 1941, a section of the Kirby Mansion became part of the Cornelius Vanderbilt Residence in Old Westbury

The Kirby Mansion is still part of the wing of the Old Westbury Country Club.