_Natural forces._—Such natural agencies for producing wealth are seen in the simple properties of material bodies, such as the metals or woods or grains or fruits or flowers possess. We secure these properties for our uses. Gravity, sound, heat, light, electricity, chemical affinity, crystallization, even life itself, are names for certain forms of energy in nature which men are using more or less to meet their wants. Whenever exertion is needed to provide for using these, the thought of wealth is connected with the forces themselves. The fish in the sea and rivers become wealth to one who has caught them, and even more distinctly the property of the community which has protected them in breeding. Sunlight may reach all alike in welfare, but the man who has contrived to make it print pictures for him has made sunlight into wealth in the picture. Equally so the farmer’s energy and contrivance use the properties of soil and climate and the vital energies of seeds to make wealth in a crop. _Control for welfare._—As each individual worker gains control over any of these properties or forces he advances in wealth and welfare. It becomes his own means of meeting wants. If all individuals in a community share in such control, they think of the good things as part of the general welfare, and do not enumerate them in anybody’s wealth except when comparing their own condition with that of another community. Advantages of this kind constantly tend to become more universal, and so to count very little in individual wealth. Many advantages of civilization today belong to all the world alike, so that nature seems to meet our wants gratuitously; but the story of progress shows that these are gifts inherited from the wealth of past ages. The human exertion which they once cost is overlooked in the ease of the present. Mere fire was once a treasure to be cherished and kept at much expenditure of strength and foresight. Now we kindle a fire so easily that nobody thinks of it as a part of the world’s wealth. _Land as a force._—Land represents a combination of natural energies and properties so important as to be named sometimes as a distinct force in production. It implies, first, needed space for various kinds of exertion in both country and town. Second, it includes all mineral, vegetable and animal bodies that are found above, on or under the surface. Third, it is soil, an essential part of a farmer’s equipment in using nature’s processes of growth.