The use of a thing by immediate seizure is, on its own, a single act of taking possession. But insofar as such use is grounded upon a continuing need, and consists in the repeated use of a self-renewing product — perhaps even restricting itself for the sake of preserving that renewal — these and other circumstances turn that immediate single act of seizure into a sign that it is meant to bear the significance of a universal taking of possession, and hence of the taking of possession of the elemental or organic basis, or of the other conditions of such products.