Here is a short article about an underground mining method and/or piece of equipment used to move ores. Mining in Manitoba says this about Slusher Mining:

Although not an actual mining method, the use of slushers for removing ore from drawpoints and pillar stopes was common in the past. A slusher is essentially a double drum hoist. Slushers may have either electric or compressed air motors of 5 to 125 hp. One cable of the slusher is attached to the front of the scraper so that it can be pulled towards the slusher and an orepass. The other cable goes around a block securely fastened in the far end of the slusher drift or pillar and is attached to the back of the scraper. Pulling this cable brings the bucket toward the end of the drift or pillar for another load. As the scraper is dragged across the muck pile, the ore is pulled into an ore pass or into an ore car.

The only supplier of Slusher Hoists that I found on InfoMine via the keyword search is Faure Equipment in France. I could not find the equipment on their website though. Via Google I found Pacific Industrial Supply who sells slusher rope. Then I was reminded that I could type in the equipment type, so from InfoMine Suppliers I got eighteen suppliers of slushers. I found slushers on only these: MiningEquipment.com, Nelmaco Eastern, Atlas Mine and Mill Supply, and R.A. Warren Equipment. I am sure the other companies listed have them, but I did not have the patience to wade through the multiplicity of things on their websites to find what is obviously an obscure piece of machinery.

The Stillwater Mining Company uses what they call "selective (slusher) mining". According to one of our readers, the Noranda GECO mine also used slushers for most of its existence. In the book An Old Man Remembers The Way it Was, is the term slusher drift. At this point I stopped, for I was wandering into those fascinating by-ways of the internet where you read adverts from 1952 for job openings for Slusher Operators in Shropshire. On the historical bye-ways of the internet, here are two links to old pieces about slushers and similar in mines: Compressed Air Magazine from 1921 and Compressed Air (undated, but old).

Before I turned from the subject, I tried to establish the origin of the word. The Navy uses the term to describe a shipmate who loans money at interest rates that would make a mafioso blush. And if you blush easily, stop reading now. But if you have a just sense of the wry, and a deep interest in the infinite variety of the meaning of words, proceed at your own risk. The Urban Dictionary definition [be advised - adult content] has a most unusual definition of the word. Maybe the word comes from the simpler slush, which is speculated to be of Scandinavian origin, maybe related to the Norwegian word slask meaning sloppy weather. The on-line dictionaries are mostly silent on both slush and slusher—if you know more, please let me know.