Dr. Morton was a dentist who, in 1841, introduced a new kind of solder by which false teeth could be fastened to gold plates. Then, in the endeavor to extract teeth without pain, he tried stimulants, opium and magnetism without success, and finally sulphuric ether. On September 30, 1846, he administered ether to a patient and removed a tooth without pain; the next day he repeated the experiment, and the next. Then, filled with the immense possibilities of his discovery, he went to Dr. J. C. Warren, one of the foremost surgeons of Boston, and asked permission to test it decisively on one of the patients at the Boston hospital during a severe operation. The request was granted, and on October 16, 1846, the test was made in the presence of a large body of surgeons and students. The patient slept quietly while the surgeon's knife was plied, and awoke to an astonished comprehension that the dreadful ordeal was over. The impossible, the miraculous, had been accomplished; suffering mankind had received such a blessing as it had never received before, and American surgery had scored its greatest triumph. Swiftly as steam could carry it, the splendid news was heralded to all the world, and its truth was soon established by repeated experiments. To tell of the work of the men who came after these pioneers in the field of surgery and medicine is a task quite beyond the compass of this little volume. There are at least a score whose achievements are of the first importance, and nowhere in the world has this great science, which has for its aim the alleviation of human suffering, reached a higher development. Among the physicists of the country, Joseph Henry takes a high place. His boyhood and youth were passed in a struggle for existence. He was placed in a store at the age of ten, and remained there for five years. At the age of fifteen he was apprenticed to a watchmaker, and had some thought of studying for the stage, but during a brief illness, he started to read Dr. Gregory's "Lectures on Experimental Philosophy, Astronomy and Chemistry," and forthwith decided to become a scientist. He began to study in the evenings, managed to take a course of instruction at the academy at Albany, New York, and finally, in 1826, was made professor of mathematics there.