Page:Popular Science Monthly Volume 41.djvu/68

58 modulus. One of the chief objects of study in physical anthropology is the skull, and it is important to have some convenient means of comparing skulls of different kinds. To compare measurements taken in one direction only, of course gives no results of value; thus, to know that one skull is nine and another is eight inches long, tells nothing as to shape or relative capacity. Authors accordingly devised the cranial index, found by dividing the length of the skull into the breadth and expressing the result decimally. If skulls had but two dimensions this index would be satisfactory; as it is, it is not perfect. A new index was devised which should take account of the height of the skull; the height being divided by the length and the result expressed decimally. By a combination of these two indices a fair idea of the skull would be given, but in a comparison of the indices of a number of skulls great difficulty arises. One expression is what is desired. After much careful study and experimental work, Prof. Schmidt worked out the modulus; the length, breadth, and height are measured and their arithmetical mean is taken.

A veteran worker is Dr. Herman Welcker, Director of the Anatomical Laboratory of the University of Halle. The building he occupies is one of the few in Europe that has been built recently and for scientific purposes. Welcker's work extends back through many years, and, although all of his suggestions have not been accepted by other workers, his contributions to craniology have been numerous and valuable. In the museum under his charge is a wonderful series of skulls, especially rich in Papuan, South sea island, and Indian specimens. One noticeable feature of the museum is the exceedingly large collection of human monsters, two-headed, cyclopean, etc. perhaps the largest in the world.

No physical anthropologist in Europe is more widely known or more respected than Dr. Rudolph Virchow, of Berlin. He is in charge of the Pathological Institute of the university, where he has a vast quantity of valuable material. Among other osteological collections are great numbers of skeletons and skulls of the Negrito pygmies. Virchow's writings have been extensive and most important. He is at present engaged upon a great work a study of crania of American Indians, from both the Northern and Southern continents. An atlas of plates will form a part of the work, and every skull will be represented as seen from five different positions. The matter of fixing a skull in position for drawing is one of no little importance, and unfortunately there is no agreement between French and German workers in regard to what shall be called the horizontal line. The French consider a line drawn from the occipital foramen to a point between