Carved on each side of the niche above the keystone is a "true-lover's-knot." A cynical observer (Rider's "New York City") comments: "Few visitors note the sly touch of irony which, by a few strokes of the chisel, has converted the lover's knot on the northerly side into an unmistakable dollar sign." On the west side of the Avenue, running from Fifty-first to Fifty-second, are the Vanderbilt twin residences, the wonder of the town of a quarter of a century ago.

They were built, in 1882, by the late William H.Vanderbilt, the southerly for his own use, and the northerly one for his daughter, Mrs.William D.Sloane.In 1868 the land on which the brown-stone mansions stand was occupied by one Isaiah Keyser, whose small three-story frame house was in the middle of a vegetable garden.
That garden supplied the residents along lower Fifth Avenue, and its owner also dealt in ice and cattle.

In the house which Mr.Vanderbilt erected for himself Henry C.Frick lived for a time.

The Vanderbilt family spent millions of dollars in purchasing property to protect themselves against business encroachments.
In former days the neighbourhood was given over largely to philanthropic and religious institutions.

The New York Institution for the Instruction of the Deaf and Dumb stood between Forty-eighth and Fiftieth Streets and Fourth and Fifth Avenues.