[Frederic Shonnard & W.W. Spooner (1900)] He promptly began to improve his estate. About 1700 he dammed Tippet's Brook, thus creating the present Van Cortlandt Lake; and probably not long afterward he erected below the dam the Van Cortlandt mill, which until as recent a date as 1889 (when it came into the posses-sion of the City of Xew York) continued to grind corn for the neighbor-ing farmers. Jacobus in his will bequeathed to his only son, Fred-erick Van Cortlandt, his farm, " situate, lying, and being in a place 274 HISTORY OF WESTCHESTER county commonly called and known by the name of Little or Lower Yonck-ers." Frederick (bora in 1698) married Francina, daughter of Au-gustus and Anna Maria (Bayard).Jay, whereby his descendants be-came of kin to Chief Justice John Jay. It was under Frederick's pro-prietorship thai the Van Cortlandt mansion now in the custody of the Colonial Dames — a dwelling winch rivals the Philipse Manor house at Yonkers as a specimen of high-class colonial architecture, and, like the latter, is still in a state of perfect preservation — was con-structed. The Van Cortlandt Mansion ( we quote from the interesting descriptive pamphlet pub-lished by its present custodians) is built of rubble stone, with brick trimmings about the windows. It is unpretentious in appearance, yet possessing-a stateliness all its own, which grows upon the visitor.