nearer accomplishment than at the end of the last quarter-century. But the time will yet come, we at least may reasonably hope, if not predict, when a way will be found thus to increase the availability of the stored energy of our fuel deposits, until they shall furnish ten times the power and energy now obtainable from each ton of fuel; thus correspondingly lengthening the period of human life and work in the temperate regions of the earth. Were this to-day possible, the endurance of the Pennsylvania coal-beds as sources of power would be lengthened from the present anticipated century to a millennium, and the thirtieth century, instead of only the twentieth, would profit by them. Great Britain might hope to continue a manufacturing nation for five centuries to come, and the world might gain ten times as much permanent wealth, by its use of the latent energy of fuel, as now seems possible.
The mechanical engineer, the electrician and the chemist have here an incentive to a most magnificent task and a noble rivalry.
The second of our great triumvirate of inventors or discoverers is more certainly coming. His advent is indicated by the electrical engineer and the physicist in their use of electrical energy of enormously high tension; while the biological chemist is now a close second in the race, through his researches in the field of low-temperature combustion and amongst the animal forms producing light and electricity without heat—the animal machines in which the processes of nature are seen already accomplishing the task. This being done, the engineer will be able to reduce the cost of lighting, as measured in power, to one-twentieth its present amount, and as measured in fuel, if he can combine these two improvements effectively, to one-two-hundredth its amount to-day, proportionally reducing the intimidating waste now going on in our deposits of irreplaceable natural stores of power.
The third inventor is also here with a crude beginning of his task, and while, at the commencement of the nineteenth century, he was a subject of unsparing ridicule, and even sometimes by able men within the last decade, he would be a bold man who should to-day dare to assert the improbability of the coming century seeing the problem solved, so far as its engineering is concerned. The commercial problem must be left to take care of itself—as it always has done hitherto.
All these are evidently problems affecting vitally all progress in the future of energy-production in the field of mechanical engineering. When complete conversion of energy is effected by any mechanism employing our natural sources of energy, the task of the builder of the air-ship is rendered less difficult, the cost of light-production is made easier and the utilization of the latent energy of fuel through the heat-engine is made comparatively insignificant in cost.
This much is revealed to us through 'The Great Discovery of the Age,' as some one has rightly called it: the discovery and experimentally
