On Tuesday, Senate Majority Leader Mitch McConnell pushed back the start of August recess until the third week of August, to give his colleagues more time to work on health care reform legislation and chip away at the backlog of executive and judicial nominees. (The House has no plans to do the same, but Majority Leader Kevin McCarthy told Politico on Wednesday that representatives would plan to return if the Senate bill passes.) It's a move that has been used before — but it was only relatively recently that the mechanisms for making such a decision changed.

That's not to say that the idea of a recess — which many members of Congress see not as a summer vacation, but rather as a chance to spend quality time with constituents — is a new one. Congress has long seen August as an ideal month for housekeeping in members' districts, and for a simple reason: It's too darn hot.

Throughout most of the 19th century and up until the mid-20th century, it was typical for Congress to be in session only from December to May, as being a member of Congress was seen as a part-time job. And it was no accident that that half of the year was chosen. Though there were many reasons for the Founding Fathers to choose to put their new nation's capital in Washington, D.C., the climate was not one of them. Even foreign ambassadors wouldn't go to Washington unless they got some kind of bonus, Congressional history expert David King once told The Daily Beast. John Nance Garner, who was House Speaker before becoming FDR's Vice President in 1933, was famous for saying, “No good legislation ever comes out of Washington after June.”