View of the Southern Facade of the White House in Washington, D.C. (1800's)

View of the southern facade of the White House in Washington, D.C., c. 1800's. By W.W. Lytle.

Source.

A sharper print of the photograph I came across recently.

Source.

Recently Uncovered Photograph of the Smithsonian Castle Under Construction in Washington, D.C. (1850)

Recently uncovered photograph of the Smithsonian Castle under construction in Washington, D.C., June/July 1850. Believed to be the earliest photograph of the Smithsonian Castle. By the Langenheim brothers.

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Two Daguerreotype Views of the General Post Office in Washington, D.C. (1846)

Two daguerreotype views of the General Post Office in Washington, D.C., c. 1846. Probably taken in different seasons judging from the difference in the amount of leaves in the trees. By John Plumbe, Jr. The building survives today as the Hotel Monaco.

Source 1.
Source 2.