In the work there is also a reference or assignment to 'materials': the work is dependent on [angewiesen auf] leather, thread, needles, and the like. Leather, moreover is produced from hides. These are taken from animals, which someone else has raised. Animals also occur within the world without having been raised at all; and, in a way, these entities still produce themselves even when they have been raised. So in the environment certain entities become accessible which are always ready-to-hand, but which, in themselves, do not need to be produced. Hammer, tongs, and needle, refer in themselves to steel, iron, metal, mineral, wood, in that they consist of these. In equipment that is used, 'Nature' is discovered along with it by that use—the 'Nature' we find in natural products.
Here, however, "Nature" is not to be understood as that which is just present-at-hand, nor as the power of Nature. The wood is a forest of timber, the mountain a quarry of rock; the river is water-power, the wind is wind 'in the sails'. As the 'environment' is discovered, the 'Nature' thus discovered is encountered too. If its kind of Being as ready-to-hand is disregarded, this 'Nature' itself can be discovered and defined simply in its pure presence-at-hand. But when this happens, the Nature which 'stirs and strives', which assails us and enthralls us as landscape, remains hidden. The botanist's plants are not the flowers of the hedgerow; the 'source' which the geographer establishes for a river is not the 'springhead in the dale'.
The work produced refers not only to the "towards-which" of its usability and the "whereof" of which it consists: under simple craft conditions it also has an assignment to the person who is to use it or wear  it. The work is cut to his figure; he 'is' there along with it as the work emerges. Even when goods are produced by the dozen, this constitutive assignment is by no means lacking; it is merely indefinite, and points to the random, the average. Thus along with the work, we encounter not only entities ready-to-hand but also entities with Dasein's kind of Being—entities for which, in their concern, the product becomes ready-to-hand; and together with these we encounter the world in which wearers and users live, which is at the same time ours. Any work with which one concerns oneself is ready-to-hand not only in the domestic world of the workshop but also in the public world. Along with the public world, the environing Nature [die Umweltnatur] is discovered and is accessible to everyone. In roads, streets, bridges, buildings, our concern discovers Nature as having some definite direction. A covered railway platform takes account of bad weather; an installation for public lighting takes account of the darkness, or rather of specific changes in the presence or absence of daylight-the 'position of the sun'.