They selected Scarboro because both of them could play golf, and they planned that their first skirmish should be fought and won upon the golf-links of the Sleepy Hollow Country Club.
But the attack did not succeed.

Something went wrong.

They began to fear that the lady correspondent had given them the wrong dope.

For, although three months had passed, and they had played golf together until they were as loath to clasp a golf club as a red-hot poker, they knew no one, and no one knew them.

That is, they did not know the Van Wardens; and if you lived at Scarboro and were not recognized by the Van Wardens, you were not to be found on any map.
Since the days of Hendrik Hudson the country-seat of the Van Wardens had looked down upon the river that bears his name, and ever since those days the Van Wardens had looked down upon everybody else.