Shortly after 1866, Mrs. Eddy declared to many people that she had made a discovery which enabled her to cure the sick with Divine aid, and without the use of drugs. She healed many people and gradually gathered followers. In a few years, she developed a religion that is now called Christian Science; and in 1875 she published a book called "Science and Health, with Key to the Scriptures." Since then, the number of her followers has increased enormously, and Christian Science Churches have been erected in all the civilized countries of the world. Though the doctrines of Christian Science have not been accepted by many Christians, the great opposition directed toward them at first has now been largely overcome; and it is admitted by most fair-minded people that Christian Science seems to have made an important contribution to the spiritual, mental and physical welfare of mankind. In 1868, Westinghouse made his epochal invention, the railway air-brake. It was the result of a brilliant mental conception that was put into practical form without very serious difficulty. At first sight, this invention might not be considered of very great importance, because one might assume that its only office was to prevent collisions and consequent loss of life and property. Doubtless that was its only direct effect; but its indirect effect was to increase the confidence of the people in the safety of railway travel, consequently the number of people who traveled, consequently the prosperity of the railway companies, consequently the faith of people in railway investments, consequently the number and magnitude of railway projects, consequently the number and length of railways, consequently the speed and general excellence of transportation and communication over the land in every civilized country, and consequently the coherency and operativeness of the entire Machine. CHAPTER XII INVENTION OF THE MODERN MILITARY MACHINE, TELEPHONE, PHONOGRAPH, AND PREVENTIVE MEDICINE In 1866, one of the most important inventions of history was put to test, in a war between Austria and Prussia. The invention was the Prussian Military Machine, of which the inventor was von Moltke, the Chief of Staff of the Prussian Army. Moltke was not the original inventor of the Military Machine, any more than Watt was the original inventor of the steam engine; but he was the inventor of the modern Military Machine, just as Watt was the inventor of the modern reciprocating steam-engine.