sluice box vs swab

sluice box

noun
  • A box with riffles along the bottom, used to trap heavier gold particles as water washes them and the other material along the box. 

swab

noun
  • A piece of material used for cleaning or sampling other items like musical instruments or guns. 

  • A sailor; a swabby. 

  • A naval officer's epaulet. 

  • A small piece of soft, absorbent material, such as gauze, used to clean wounds, apply medicine, or take samples of body fluids. Often attached to a stick or wire to aid access. 

  • A mop, especially on a ship. 

  • A sample taken with a swab (piece of absorbent material). 

verb
  • To use a swab on something, or clean something with a swab. 

How often have the words sluice box and swab occurred in a corpus of books? (source: Google Ngram Viewer )