Document zd45Q03oBgZY48nKGL4JZD7En

June 1938 372 /. V. Sparks microscopically by dark ground illumination, the fibre gives the impression of a sharp, brittle, metallic wire, broken off at different angles and in different lengths; and, being highly refractile, it has the appearance of the glowing filament of an electric bulb. Chemically it is a silicate of iron and magnesium, and does not contain a free silica. The Shape of the Particles Inhaled The shape of the asbestos particles inhaled causes them to be arrested in the terminal bronchioles, and a deposit of iron-containing material forms over Fic. 2. Female, aged 27. Asbestos Worker 6 years; symptoms developed 3^ years after leaving factory. them. These are now known as the "Asbestos Bodies," first recognised by Fahr in 1914, and called "crystals." They were subsequently described in 1927 by Cooke and Hill, and Stuart McDonald as "curious bodies,'' found in the lungs of asbestos workers. Later in 1929, Stuart and Haddow made the suggestion that the bodies should be called "Asbestosis Bodies"; and it was Gloyne.in 1929, who showed that the central core of the body consisted of an asbestos fibre coated with a substance soluble in strong acid. They are of a golden-yellow colour, and vary considerably in size and shape. These bodies are produced as a tissue reaction to the inhalation of the asbestos fibre; the covering is thought to be protective.