know. Just as road friction is the bugbear of the railway engineer, so water-resistance is the bugbear of the marine engineer. The ships of a hundred years hence will not lie in the water, They will tower above the surface, merely skimming it with their keels, and the only engines they will carry will be those which receive and utilise the energy transmitted to them from the power-houses ashore—perhaps worked by the force of the very tides of the conquered ocean itself.
The housing problem is so intimately and visibly connected in our minds with the growth of population that the more vital entanglement of the latter with the food question is hardly perceptible except to economic experts. The ordinary newspaper reader is not in a position to trace the intimate significance of prices; indeed, he often regards it as rather a good thing that wheat should fetch a good price per quarter, forgetting that low prices for commodities mean increased purchasing power for money, and a better standard of life for the people. When such elementary implications as this are overlooked, it is hardly remarkable that the more obscure connection of population with prices is never thought of. Yet it is obvious that unless the sources of supply increase more rapidly than the consuming population, prices must rise—in other words, the purchasing power of money must diminish.
