292 REVIEWS 
It is thought probable that coal was first used in Britain by the 
early Bretons, but direct evidence of it is wanting. However, it is 
known to have been used by the Roman invaders, as cinders and coal 
ashes have been found in the ruins of the Roman houses. Not 
much is known of the coal industry from the time of the Roman inva- 
sion until the beginning of the thirteenth century when it is referred 
to in certain land grants. ‘The first mines were located in the vicinity 
of Newcastle. By the year 1379 coal had become of sufficient impor- 
tance to make it an object of impost. By the beginning of the six- 
teenth century the production had reached an average of a million 
tons per year, and the total production from that date to 1866 is esti- 
mated to be 850 million tons. . 
The principal coal beds of the United Kingdom occur in the Coal 
Measures or upper part of the Carboniferous series. According to 
Hull the Lower Carboniferous has a threefold division: (1) the lower 
schist group, (2) the Mountain limestone, and (3) the Yoredale group. 
The Upper Carboniferous is divided into (1) the Millstone grit, (2) the 
lower Coal Measures, (3) the middle Coal Measures, and (4) the upper 
Coal Measures. The last three divisions contain the productive coal 
beds. The work is accompanied by maps locating accurately the 
known coal areas and giving the probable extent of the undetermined 
ones. 
The coals of Britain are classed under the heads of: 
1. Lignites, containing 67 per cent. of carbon and 26 per cent. of 
oxygen. 
2. Bituminous coal, containing 75 to go per cent. of carbon and 6 to 
Ig per cent. of oxygen. 
3. Steam coal, a sort of semi-anthracite. 
4. Cannel coal, containing 4o per cent. of volatile matter and being 
rich in hydrogen. 
5. Anthracite coal, containing 93 to 95 per cent. of carbon and 3 per 
cent. of oxygen with 2 to 4 per cent. of hydrogen. 
The total exportation of coal from the British Isles in 1898 was 35 
million tons, which was a decrease over the preceding year of about 
300,000 tons. The importation of coal for 1897 was only 9454 tons. 
The amount of coal consumed per capita in 1898 was 3.867 tons. 
The author discusses the estimate made by the Commission of 
1870, that the coal resources of the United Kingdom are 80 billion 
tons, and that at the present rate of depletion (2 million tons per year) 
