James Dwight Dana was attracted to Yale by Prof. Silliman's great reputation and received there the inspiration which started him upon a scientific career. Three years after his graduation, he was appointed assistant to his former instructor, and two years later sailed for the South Seas as mineralogist and geologist of the United States exploring expedition commanded by Charles Wilkes. He was absent for three years and spent thirteen more in studying and classifying the material he had collected. He then resumed his work at Yale, succeeding Prof. Silliman in the chair of geology and mineralogy. His work was recognized throughout the world as most important, and many honors were conferred upon him.
Another famous name in American geology is that of John Strong Newberry. His name is connected principally with the explorations of the Columbia and Colorado rivers. He was afterwards appointed professor of geology and paleontology at the Columbia College School of Mines, and took charge of that department in the autumn of 1866. During his connection with the institution, he created a museum of over one hundred thousand specimens, principally collected by himself, containing the best representation of the mineral resources of the United States to be found anywhere.
Among the pupils of Prof. Silliman who afterwards won a wide reputation was Josiah Dwight Whitney. Graduating from Yale in 1839, he spent five years studying in Europe, and then, returning to America, was connected with the survey of the Lake Superior region, of Iowa, of the upper Missouri, and of California, issuing a number of books giving the results of these investigations, and in 1865, being called to the chair of geology at Harvard.
Still another of Prof. Silliman's pupils was Edward Hitchcock, whose life was an unusually interesting one. His parents were poor and he spent his boyhood working on a farm or as a carpenter, gaining such education as he could by studying at night. Deciding to enter the ministry, he managed to work his way through Yale theological seminary, graduating at the age of twenty-seven. It was here that he came under the influence of Prof. Silliman, and after a laboratory course and much field work, he was chosen professor of chemistry and natural history at Amherst College. He held this position for twenty years, and in 1845 was chosen president of the college, transforming it, before his retirement nine years later, from a poor and struggling institution into a well-endowed and firmly established one. He had meanwhile served as state geologist of Massachusetts, and completed the first survey of an entire state ever made by authority of a government.
The most important recent contribution to American geology has been the three volume work issued in 1904-5, under the joint editorship of Thomas C. Chamberlain and Rollin D. Salisbury. Both are geologists of wide experience, and their work presents the present status of the science interestingly and simply.
America has had her full share of daring and successful surgeons, and in the science of surgery stands to-day second to no nation on earth, but perhaps the most famous American surgeon who ever lived was Valentine Mott. Dr. Mott was descended from a long line of Quaker ancestors, and was born in 1785. His father was a physician, and Dr. Mott began his medical and surgical studies at the age of nineteen, first in New York City, and afterwards in the hospitals of London, where he made a specialty of the study of practical anatomy by the method of dissection. At that time there was in this country a deep-seated prejudice against the use of the human body for this purpose, and the experience which Dr. Mott secured in London, and which stood him in such good stead in after years, would have been impossible of attainment here. A year was also spent in Edinburgh, and finally, in 1809, Dr. Mott returned to America with an exceptional equipment.
His skill won him a wide reputation and he was soon recognized as one of the first surgeons of the age. His boldness and originality were exceptional, and his success was no doubt due in some degree to his constant practice throughout his life of performing every novel and important operation upon a cadaver before operating upon the living subject. To describe in detail the operations which he originated would be too technical for such a book as this, but many of them were of the first importance. Sir Astley Cooper said of him: "Dr. Mott has performed more of the great operations than any man living, or that ever did live." He possessed all the qualifications of a great operator, extraordinary keenness of sight, steadiness of nerve, and physical vigor. He could use his left hand as skillfully as his right, and developed a dexterity which has never been surpassed.
It should be remembered that in those days the use of anæsthetics had not yet been discovered, and every operation had to be performed upon the conscious subject, as he lay strapped upon the table shrieking with agony. To perform an operation under such circumstances required an iron nerve. Dr. Mott was one of the first to recognize the value of anæsthetics, and his use of them, immediately following their discovery, greatly facilitated their rapid and general introduction.
It is one of the boasts of American medicine that the first man in the world to conceive the idea that the administration of a definite drug might render a surgical operation painless was an American—Crawford W. Long. Dr. Long graduated from the medical department of the University of Pennsylvania in 1839. When a student, he had once inhaled ether for its intoxicant effects, and while partially under the influence of the drug, had noticed that a chance blow to his shin produced no pain. This gave him the idea that ether might be used in surgical operations, and on March 30, 1842, at Jefferson, Georgia, he used it with entire success. He repeated the experiment several times, but he did not entirely trust the evidence of these experiments. So he delayed announcing the discovery until he had subjected it to further tests, and while these experiments were going on, another American, Dr. W. T. G. Morton, of Boston, also hit upon the great discovery and announced it to the world.