Stock raising is more patently influenced by and dependent upon its physical environment than most other industries appear to be. The topographic and climatic conditions are fundamental because they determine the kind and quantity of feed the animals must eat, the temperature and other extremes they must endure, and the various dangers which they must avoid. The laws and customs of the region determine the character of the tenure and control of the land that produces the feed upon which the animals subsist. They are but the expression of public opinion that warrants the existence of that industry in that place. And not less important, but probably less often considered, is the relation that the business bears to other industries in operation in the same region. From this standpoint, the industry is to be considered as in a certain stage of development toward a better and more complex adjustment among all industries, and a statement of its present condition must be taken as in the nature of a report of progress. It is not what it once was, nor yet what it will be. Thus, while we are here mainly concerned with the details of the purely physical basis of the industry, the factors of control and relation to other industries are so closely connected with any proper kind of management that they must be considered somewhat at length. A study of range conditions is but preliminary to an understanding of methods of management and the requirements necessary for the further improvement of the industry.