A firm believer in the truth of his theories, he devoted the last fifteen years of his life and $100,000 to experimental work on his solar engine. For various reasons Ericsson's invention was not a practical success; but now that modern inventors, with their advancing knowledge of mechanics, have turned their attention to the problem, and now that the need of the solar motor is greater than ever before, especially in the world's deserts, we may look to see a practical and successful machine. Perhaps the California motor may prove the solution of the problem; perhaps it will need improvements, which use and experience will indicate; perhaps it may be left for a reader of these words to discover the great secret and make his fortune.
CHAPTER VI
THE INVENTOR AND THE FOOD PROBLEM
Fixing of Nitrogen—Experiments of Professor Nobbe
No lad of to-day, ambitious to become a scientist or inventor, reading of all the wonderful and revolutionising discoveries and inventions of recent years, need fear for plenty of new problems to solve in the future. No, the great problems have not all been solved. We have the steam-engine, the electric motor, the telegraph, the telephone, the air-ship, but not one of them is perfect, not one that does not bring to the attention of inventors scores of entirely new problems for solution. The further we advance in science and mechanics the further we see into the marvels of our wonderful earth and of our life, and the more there is for us to do.
As population increases and people become more intelligent there is a constant demand for new things, new machinery which will enable the human race to move more rapidly and crowd more work and more pleasure into our short human life. One man working to-day with machinery can accomplish as much as many men of a hundred years ago; he can live in a house that would then have been a palace; enjoy advantages of education, amusement, luxury, that would then have been possible only to kings and princes.
And the very greatest of all the problems which the inventors and scientists of coming generations must solve is the question—seemingly commonplace—of food.
We who live in this age of plenty can hardly realise that food could ever be a problem. But far-sighted scientists have already begun to look forward to the time when there will be so many people on the earth that the farms and fields will not supply food for every one. It is a well-known fact that the population of the world is increasing enormously. Think how America has been expanding; a whole continent overrun and settled almost within a century and a half! Nearly all the land that can be successfully farmed has already been taken up, and the land in some of the older settled localities, like Virginia and the New England States, has been so steadily cropped that it is failing in fertility, so that it will not raise as much as it would years ago. In Europe no crop at all can be raised without quantities of fertiliser.
While there was yet new country to open up, while America and Australia were yet virgin soil, there was no immediate cause for alarm; but, as no less an authority than Sir William Crookes pointed out a few years ago in a lecture before the British Association, the new land has now for the most part been opened and tamed to the plough or utilised for grazing purposes. And already we are hearing of worn-out land in Dakota—the paradise of the wheat producer. The problem, therefore, is simple enough: the world is reaching the limits of its capacity for food production, while the population continues to increase enormously: how soon will starvation begin? Sir William Crookes has prophesied, I believe, that the acute stage of the problem will be reached within the next fifty years, a time when the call of the world for food cannot be supplied. If it were not for our coming inventors and scientists it would certainly be a gloomy outlook for the human race.
But science has already foreseen this problem. When Sir William Crookes gave his address he based his arguments on modern agricultural methods; he did not look forward into the future, he did not show any faith in the scientists and inventors who are to come, who are now boys, perhaps. He did not even take cognisance of the work that had already been done. For inventors and scientists are already grappling with this problem of food.
In a nutshell, the question of food production is a question of nitrogen.
This must be explained. A crop of wheat, for instance, takes from the soil certain elements to help make up the wheat berry, the straw, the roots. And the most important of all the elements it takes is nitrogen. When we eat bread we take this nitrogen that the wheat has gathered from the soil into our own bodies to build up our bones, muscles, brains. Each wheat crop takes more nitrogen from the soil, and finally, if this nitrogen is not given back to the earth in some way, wheat will no longer grow in the fields. In other words, we say the farm is "worn out," "cropped to death." The soil is there, but the precious life-giving nitrogen is gone. And so it becomes necessary every year to put back the nitrogen and the other elements which the crop takes from the soil. This purpose is accomplished by the use of fertilisers. Manure, ground bone, nitrates, guano, are put in fields to restore the nitrogen and other plant foods. In short, we are compelled to feed the soil that the soil may feed the wheat, that the wheat may feed us. You will see that it is a complete circle—like all life.