ABSTRACT
The importance of saving the tar and the ammonia which are given off by coal, when heated, together with a large quantity of inflammable gas has led to an immense amount of invention, and an almost innumerable variety of ovens have been devised with the object of recovering and utilising these by-products. One of the first contrivances introduced was the coke oven known as Jameson’s. For the purpose of generating combustible gas a variety of systems have been adopted by which air in limited quantity is drawn or driven through a mass of red-hot coal contained in a firebrick chamber called a “gas-producer.” A gas of this kind contains about one-third of its volume of carbonic oxide mixed with nitrogen from the air and a little carbon dioxide. Crude coal-tar finds some applications without being separated by distillation into its components.
