Disease at the National?

[L Verge]

Your question intrigued me, Maddie, so I did a quick check on the history of plumbing. Does the Tremont Hotel in Boston still exist? Its architect, Isaiah Rogers, actually designed it to have indoor plumbing as early as 1829. It had eight "water closets" on the ground floor near the rear of the central court. There were also bathrooms (for bathing) in the basement with cold water pumped into tubs where it was then heated by small, side-arm, gas heaters.

In 1834, the same Mr Rogers worked his magic in New York City with his new Astor House. That hotel had 17 rooms with water closets and enough bathrooms to accommodate 300 guests.

It's late, but I'll try to track down some more info tomorrow. I suspect Betty's answer, however, applies to 90% of the establishments during the Civil War.