The people inhabiting Central Asia domesticated animals of various kinds from which the domestic cow, sheep, goat, camel and horse have been developed through selection of certain types for breeding. Much of the country in that part of the world is too dry at times during the summer to make possible any reasonable degree of certainty of the outcome of the cultivation of crops, and is to-day largely tenanted by pastoral tribes. It was in the semi-arid regions of Asia that the earliest advances toward achievement were made. We see in certain of the pastoral Arab tribes to-day, people who are living much as have their ancestors and those of their neighbors, for hundreds of generations. The Arabs are physically as fine a people as any in the world. They are singularly free from physical defects, and present the ideal of physical beauty in a remarkable number of individuals who are not disfigured by the date boil or Aleppo button which is caused by an infection in the face, usually occurring during childhood. They live in a climate which is inhospitable a large part of the year because of excessively high temperatures. They have contended with drought and scanty pastures from time immemorial, yet they are a vigorous and virile people. Deformities are very rare among them, and their children do not suffer from skeletal abnormalities characteristic of rickets as do so large a proportion of those of Europe and America. Not only are the Arabs well developed and athletic, but they have the courage to care for their flocks and herds under the most trying conditions. Actuated by the desire to trade or to carry on warfare, or stimulated by religious zeal to visit the holy cities of the Mahometans, they have undertaken long and tiresome voyages over the parched deserts. No people can have such a history, who have not had a diet which closely approached the optimal relations in respect to all its parts.