Coal was first brought into use in London about 1300, and owing to the high price of wood it rapidly came into general use. The smoke given off, on account of its imperfect combustion, became the subject of agitation in the time of Edward I, and again during the reign of Queen Elizabeth, when Proclamations were issued prohibiting the use of coal in London when Parliament was in Session. In 1306 a Royal Proclamation was issued prohibiting artificers from using coal in their furnaces upon the pains of punishment of great fines and ransoms for the first offence. In December 1799, John Frederick Chabannes was granted a patent for the manufacture of patent fuel, consisting of great and small coals mixed together which were usually bought in the pool in the
River Thames for consumption in the cities of London and Westminster and their environs. The composition consisted of small coals and a small quantity of earth, clay, cow-dung, tar, pitch, broken glass, sulphur, sawdust, oil-cakes, tan, or wood, mixed together and moulded into bricks or balls. This better and last recipe was practically dirt-free and smokeless. Patent fuel was the second most popular exported product in Wales. During 1913 Wales exported 746,000 tons of iron and 714,000 tons of Patent fuel. This popularity was due to its resistance in very hot or very cold climates. With coals varying from the Bituminous seams of Monmouthshire, containing up to 35 per cent., to the Anthracite seams of Carmarthenshire, having 5 per cent, of volatile matter, the blending can be adapted to a variety of conditions. Chief consumers were America, French, Italy and Spanish railway and steamship companies. == Process of manufacture ==