BBB Etymology - Slush Fund
In the early 1800s, fried salt pork was a staple food aboard ships. At the end of a voyage, the grease at the bottom of the salted beef or pork rations, called "slush," was sold to candle and soap makers. The money usually helped provide little extras that the crew couldn't otherwise afford, hence the term "slush fund."
By the way, the term "pork-barrel," likely is derived from the same origin., though it's present meaning was "popularized" by E.K. Hale in his 1865 story "Pork Barrel": "When plantation owners rolled out a barrel of salt pork into the slave quarters the desperate slaves engaged in a feeding frenzy to get the best pieces. It was a form of entertainment for heartless slavelords and their guests."
By the way, the term "pork-barrel," likely is derived from the same origin., though it's present meaning was "popularized" by E.K. Hale in his 1865 story "Pork Barrel": "When plantation owners rolled out a barrel of salt pork into the slave quarters the desperate slaves engaged in a feeding frenzy to get the best pieces. It was a form of entertainment for heartless slavelords and their guests."