I have mentioned this "little" issue before, so, naturally, just wanted to suggest a combined effort of sorts. When was the earliest known photograph of the United States Government in session taken? I keep on running into nothing but drawings. The best I could come up with was this 1874 (allegedly) photograph of the 43rd US Congress posing on the stairs of the Capitol Building in Washington DC. Stairs...

19th century photographs of the US Government in session prior to 1865. Where are they?