Full Idea
A law might have no instances at all; for example, about the chemical and electrical behaviour of the transuranic elements, which only exist briefly in laboratories.
Clarification
'Transuranic' means beyond uranium (92) in the periodic table
Gist of Idea
A law might have no instances, if it was about things that only exist momentarily
Source
Alexander Bird (Philosophy of Science [1998], Ch.1)
Book Reference
Bird,Alexander: 'Philosophy of Science' [UCL Press 2000], p.31
A Reaction
Nice example. We need to distinguish, though, (as Bird reminds us) between laws and theories. We have no theories in this area, but there are counterfactual truths about what the transuranic elements would do in certain circumstances.