File:Senator Sumner's Reception Room, by E. & H.T. Anthony (Firm).jpg

English: From 1867 until his death, Charles Sumner lived in a house (built that year) on the northwest corner of H street and Vermont Avenue ( corner). Prior to that, his main residence was the Charles Sumner House in Boston.

There is a description and engraving of the house in The Life and Times of Charles Sumner by Elias Nason; it describes a multitude of fine arts that Sumner collected and brought there, which fits the picture. If the "reception room" is the one where you walk in, that would seem to make sense: the photographer would have walked in the door, turned right, and taken the photo (as the door was on the left side of the room, looks like). It also appears the right-hand wall on the back room is not as deep as the room the photographer is standing in, which also matches the image of the house -- the center portion is closer to the street. So, I'm guessing this is that house. In 1869, Corcoran built the Arlington Hotel next door, on the corner of Vermont & I Street. Some views of that here on the Streets of Washington blog; a couple of these have Sumner's house on the left side. In 1889, Corcoran bought this house, and had it attached to the Arlington Hotel as an additional wing. It sounds like the Arlington Hotel (and presumably this building too) was torn down in 1912, to make way for a bigger and better hotel, which ran into financing issues and never materialized. It sounds like the site was vacant for a few years, until the government helped finance (and later bought) a new building on the site, which is now the Department of Veterans Affairs building. A new (smaller) Arlington Hotel was built a few blocks north. - (lightly edited from remarks by Carl Lindberg, originally made at User talk:Jmabel/Stereo cards of Washington, D.C.)