theory of light, now universally accepted, the energy streaming to the earth from the sun travels through the ether on electric waves, and the heat has proved capable of being measured on the basis of horse-power per acre. As the most eminent of our physicists has pointed out, our engineers have not yet succeeded in utilising this supply of power, but science has not the slightest doubt that they will ultimately manage to do so.
At present it is the electrical energy of the sun stored up in our coal that does our work for us. Even here, however, science condemns our existing methods, root and branch, as absurdly prodigal of human labour, and as incredibly inefficient.
By our present procedure we apply effectively, as the president of the Institution of Electrical Engineers has recently pointed out, much less than 10 per cent of the energy in the coal consumed. Assuredly, the total waste of more than 90 per cent of the value of our coal in the process of conversion is an evil of magnitude. Moreover, there is a further loss, involved in our present habits of using coal, only second in importance to the above, when we dissipate, as we now do, nearly the whole of the valuable by-products contained in the coal, consisting principally of fixed nitrogen. For our best hope of eventually supplying ourselves with food-stuffs lies partly in the application of electricity, and partly in the use of those fertilisers of which fixed nitrogen is the base.
