This is a great view down East Capitol St. from the Dome, taken around 1880.

Photograph shows Carroll Row, a block of five houses at 1st & A Street, SE, razed in 1887 for construction of the Library of Congress Thomas Jefferson Building. Includes the sign “Architect.”
UPDATE: GoDCer Leonard sent along this great shot (a little blurry), from the same vantage point today. So cool!

view down East Capitol from the Dome