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This briquetting process comprises the following series of operations:

1. Mixing the finely divided material with water and newly slaked lime.

2. Pressing the mixture into blocks of the size and shape of ordinary bricks.

3. Stacking the briquettes in suitably covered kilns.

4. Burning the briquettes, so as to harden them, without melting, at the same time eliminating sulphur, arsenic, etc.

1. The material is dumped into a mixing plant, together with such proportions of screened slaked lime (usually from three to five per cent.) and water as shall produce a powdery mixture which will, on being squeezed in the hand, cohere into dry lumps. In preparing the mixture, it is well to mix sandy material with suitable proportions of fine, such as slime, in order that the finer material may act as a binding agent.

The mixer used by me consists of an iron trough, about 8 ft. long, traversed by a pair of revolving shafts, carrying a series of knives arranged screw-fashion; and so placed that the knives on one shaft travel through the spaces between the knives on the other shaft. The various materials are dumped into one end of the mixing trough, from barrows or trucks, and are delivered continuously at the other end of the trough, into an elevator which conveys the mixture to the brick-pressing plant.