A koniscope (or coniscope) is a scientific instrument to detect and measure content of dust particles in the atmosphere.Storm Dunlop: Dictionary of Weather, p. 83 A koniscope is also called dust counter, or Aitken dust counter,American Meteorological Society: Glossary of Meteorology: Aitken dust counter named after John Aitken who invented the first koniscope.
The koniscope is made by connecting a pump to a test tube that is walled with moist paper. The tube is held towards a light source and the pump is briefly activated. Dust particles will cling to the paper, producing a visible change in color.
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