Every people has two distinct lines of descent--by blood and by tradition. When we consider the physical descent of a people, we regard them purely as animals. As in any breed of animals, so in a people, the tokens of physical descent are mainly physical attributes--such as stature, complexion, the shape of the skull and members, the formation of the features. When we speak of a particular _race_ of men, if we speak accurately, we mean a collection of people whose personal appearance and bodily characters, inherited from their ancestors and perhaps modified by climate and occupation, distinguish them notably from the rest of mankind. It is important for us to be quite clear in our minds about this meaning of Race, for the word Race is often used in a very loose and very misleading way in popular writings and discussions. Thus we hear and read of the Latin races, the Teutonic race, the Anglo-Saxon race, the Celtic race. If these phrases had any value in clear thinking, they would imply that in each instance it is possible to distinguish a section of mankind which, by its inherited physical characters, differs notably from the rest of mankind. Now in not one of the instances mentioned is any such distinction known to those who have made the races of man the subject of their special study. There is no existing Latin race, no Teutonic race, no Anglo-Saxon race, and no Celtic race. Each of the groups to whom these names are popularly applied is a mixture of various races which can be distinguished, and for the most part they are a mixture of the same races, though not in every case in the same proportions. In the case of the populations which are recognised to be Celtic, it is particularly true that no distinction of race is found among them. And this is true of them even in the earliest times of their history. Tacitus, in the remarkable introductory chapters of his book, "De Moribus Germanorum," gives a brief physical description of the Germans of his time. "Their physical aspect," he says, "even in so numerous a population, is the same for all of them: fierce blue eyes, reddish hair, bodies of great size and powerful only in attack." Upon this the well-read editor of the Elzevir edition of 1573 has the following remarks: "What Tacitus says here of the Germans, the same is said by Florus and Livy in describing the Gauls.... Hence," he continues, "it appears that those ancient Gauls and Germans were remarkably similar in the nature of their bodies as well as of their minds." He goes on to develop the comparison, and sums up as follows: "Who then will deny that those earliest Celts were similar to the Germans and were in fact Germans?"