1895

John Aitkin's Koniscope and What It Has Demonstrated.

The koniscope, the invention of John Aitkin, is a useful instrument for roughly testing the purity of the atmosphere. It consists of a small metal tube about 1½ feet or 2 feet long, which is closed at the ends with pieces of glass and is connected near one end to an air pump, a stop cock near the other end admitting the air to be tested. All the shades of blue, from nearly pure white to a deep black blue, are attached alongside the tube for comparison.

As the impurities of the air or number of particles present increase the color seen through the tube deepens, a color just perceptible being given by 50,000 particles to the cable centimeter, a very pale blue by 80,000, a pale blue by 500,000, a fine blue by 1,500,000, a deep blue by 2,500,000 and a very deep blue by 4,000,000.

In making a sanitary inspection the color given by pure air is determined first and is taken as the normal health color. In tracing the pollution a air by gas flames in a room 24 by 17 by 13 foot in size Mr. Aitkin lighted three jets in the center of the room, and in 35 seconds the products of combustion had reached one end of the room, causing a sudden deepening of color in the koniscope, in four minutes the deep blue color was obtained two feet from the ceiling, and in 30 minutes the impurity nine feet from the floor was very great, the color being an intensely deep blue. — Cincinnati Commercial Gazette.