Movable types were invented, paper was borrowed from the Moors, books appeared, and it became possible to save the intellectual wealth so that each generation could hand it to the next. History began to take the place of legend and rumor. The telescope was invented. The orbits of the stars were traced, and men became citizens of the universe. The steam engine was constructed, and now steam, the great slave, does the work of hundreds of millions of men. The Black Art, the impossible, was abandoned, and chemistry, the useful, took its place. Astrology became astronomy. Kepler discovered the three great laws, one of the greatest triumphs of human genius, and our constellation became a poem, a symphony. Newton gave us the mathematical expression of the attraction of gravitation. Harvey discovered the circulation of the blood. He gave us the fact, and Draper gave us the reason. Steamships conquered the seas and railways covered the land. Houses and streets were lighted with gas. Through the invention of matches fire became the companion of man. The art of photography became known; the sun became an artist. Telegraphs and cables were invented. The lightning became a carrier of thought, and the nations became neighbors. Anaesthetics were discovered and pain was lost in sleep. Surgery became a science. The telephone was invented--the telephone that carries and deposits in listening ears the waves of words. The phonograph, that catches and retains in marks and dots and gives again the echoes of our speech. Then came electric light that fills the night with day, and all the wonderful machines that use the subtle force--the same force that leaps from the summer cloud to ravage and destroy. The Spectrum Analysis that tells us of the substance of the sun; the Röntgen rays that change the opaque to the transparent. The great thinkers demonstrated the indestructibility of force and matter--demonstrated that the indestructible could not have been created. The geologist, in rocks and deposits and mountains and continents, read a little of the story of the world--of its changes, of the glacial epoch--the story of vegetable and animal life. The biologists, through the fossil forms of life, established the antiquity of man and demonstrated the worthlessness of Holy Writ. Then came evolution, the survival of the fittest and natural selection. Thousands of mysteries were explained and science wrested the sceptre from superstition. The cell theory was advanced, and embryology was studied; the microscope discovered germs of disease and taught us how to stay the plague. These great theories and discoveries, together with countless inventions, are the children of intellectual liberty. X.