Groups of Boy Scouts often go camping and on hikes. When they do, it is a commonplace among them that John Locke's law of nature applies to interesting objects they pick up along the way. (Here I am assuming a case in which civil law does not prohibit taking the objects in question.) If one boy picks up a pretty rock that was not his at all until he picked it up, and then another boy took it out of his hands, the boy who first picked it up would say that he had stolen it. And other boys would think the same thing.
Boys do debate question such as whether it is the first one who saw a thing or the first one who got something into their own hand that can claim ownership. I think, typically, the first who saw it would have the better claim. Why? I think it is in line with John Locke's notion that the labor involved helps to establish one's claim. If the main labor is in noticing something, then noticing it (and perhaps calling dibs) would be enough to establish ownership. On the other hand, if even after noticing it, it is worthless without additional effort to extract it from the ground, say, then it would be the one who extracted it from the ground who had the better claim.
Consider how John Locke describes the principle that mixing natural bounty with one's own labor helps to establish a claim, as he lays it out in section 28 of his 2d Treatise on Government: “Of Civil Government” (Chapter V "Of Property"):
He that is nourished by the acorns he picked up under an oak, or the apples he gathered from the trees in the wood, has certainly appropriated them to himself. Nobody can deny but the nourishment is his. I ask then, when did they begin to be his? when he digested? or when he eat? or when he boiled? or when he brought them home? or when he picked them up? and it is plain, if the first gathering made them not his, nothing else could. That labour put a distinction between them and common: that added something to them more than nature, the common mother of all, had done; and so they became his private right. And will any one say, he had no right to those acorns or apples, he thus appropriated, because he had not the consent of all mankind to make them his? Was it a robbery thus to assume to himself, what belonged to all in common? If such a consent as that was necessary, man had starved, notwithstanding the plenty God had given him. We see in commons, which remain so by compact, that it is the taking any part of what is common, and removing it out of the state nature leaves it in, which begins the property; without which the common is of no use. And the taking of this or that part, does not depend on the express consent of all the commoners. Thus the grass my horse has bit; the turfs my servant has cut; and the ore I have digged in any place, where I have a right to them in common with others, become my property, without the assignation or consent of any body. The labour that was mine, removing them out of that common state they were in, hath fixed my property in them.
Despite the existence of relevant merit badges, Boy Scouts do not typically know a lot of civil law or constitutional law. But the law of nature that John Locke talks about for claiming a part of nature's bounty for one's own they do understand.
Don't miss other John Locke posts. Links at "John Locke's State of Nature and State of War."