But there was a power greater by far than that of horses, wind, or water,--a power of which poets and philosophers had long dreamt,--capable of being applied alike to the turning of mills, the raising of water, the rowing of ships, the driving of wheel-carriages, and the performance of labour in its severest forms. As early as the thirteenth century, Roger Bacon described this great new power in terms which, interpreted by the light of the present day, could only apply to the power of Steam. He anticipated that “chariots may be made so as to be moved with incalculable force, without any beast drawing them,” and that “engines of navigation might be made without oarsmen, so that the greatest river and sea ships, with only one man to steer them, may sail swifter than if they were fully manned.” But Bacon was a seer rather than an expounder, a philosophic poet rather than an inventor; and it was left to men of future times to find out the practical methods of applying the wonderful power which he had imagined and foretold. [1] Article “Government,” in ‘Encyclopædia Britannica.’ The enormous power latent in water exposed to heat had long been known. Its discovery must have been almost contemporaneous with that of fire. The expansive force of steam would be obvious on setting the first partially-closed pipkin upon the fire. If closed, the lid would be blown off; and even if the vessel were of iron, it would soon burst with appalling force. Was it possible to render so furious and apparently unmanageable an agent, docile and tractable? Even in modern times, the explosive force of steam could only be compared to that of gunpowder; and it is a curious fact, that both De Hautefeuille and Papin proposed to employ gunpowder in preference to steam in driving a piston in a cylinder, considering it to be the more manageable power of the two.