IN his presidential address on October 15 to the Institute of Fuel (see NATURE, October 31, p. 752), Sir Philip Dawson dealt with the subject of transport on land. The end of the nineteenth century may be called the electrical age, but so far as Great Britain is concerned, since electrical power is mainly produced by steam, its application to traction only means the consumption of fuel transferred from the rolling vehicle to the power-house producing electricity. In countries where electricity can be produced by water-power, this agency may largely affect the total consumption of solid and liquid fuel. Hence the French call water-power la houille blanche (white coal). We are faced to-day with the fact that, despite the high efficiency in producing light, heat and power now obtained in the combustion of coal, the output of coal in Great Britain has diminished from 287 million tons in 1913 to 223 million tons in 1935.