This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1896 Excerpt: ...dust, whilst the temperature of ignition is lower than with methane, so that when the air of the mine is charged with coal dust, the probabilities are that a very large volume of explosive mixture is formed by the rapid escape of the products of combustion into the dust, laden air, and this (lieing ignited either by the flame or by red hot solid products driven out into it by a blown out shot) initiates a considerable area of explosion. As the explosion takes place, and as the carbon monoxide already produced is oxidized to carbon dioxide by the action upon it of water vapor present, and also by its direct combustion with oxygen, the hydrogen of the water vapor is set free, whilst the heated coal dust also yields certain inflammable products of distillation to the air, and partial combustion of the coal dust gives a considerable proportion of carbon monoxide once more, and this, driven rapidly ahead of the explosion, forms, with more coal dust and air, a new explosive zone, and so, by waves and throbs, tin1 explosion is carried through the dust laden galleries of the mine. In this way any explosive which generates inflammable products of incomplete combustion is unsafe, and should never lie used even in mines where fire-damp is unknown, as such explosives are quite capable of setting up an explosion with coal dust alone. A still greater danger arises if any trace of fire-damp exists in the mine, as this, together with dust, provides an already explosive atmosphere, whilst the products evolved by blasting powder are capable of playing the same part as sulphur on a match, and causing'ignition of the explosive mixture. Fire-damp, as has been shown by the numerous experiments made since Sir Humphrey Daw's memorable researches, is not easily inflamed, and explos...