From the current issue of the always great American Heritage magazine comes a short piece by Hugh Rawson that provides the etymology of the term "pork-barrel spending," whose first usage in American political discourse dates back to around 1909.
It's an eye-opener:
The metaphor stems from the practice in the pre-refrigeration era of preserving pork in large wooden barrels of brine. The political usage may have been inspired by the distribution of rations of salt pork to slaves on plantations. "Oftenitmes the eagerness of the slaves would result in a rush upon the pork barrel, "wrote a 'journalist' named C.C. Maxey in 1919, "in which each would strive to grab as much as possible for himself. Member of Congress in the stampede to get their local appropriation items into the omnibus river and harbor bills behaved so much like negro slaves rushing the pork barrel, that these bills were facetiously styled 'pork-barrel' bills."
Rawson closes with the wonderful quote from a Senate chaplain in the early 20th century. Asked whether he prayed for the senators, the man of the cloth responded, "No, I look at the senators and pray for the country."
The full story is not yet posted at the American Heritage site, which is still certainly worthing rummaging through for a few hours on any given day.