Read it through once

It will readily be seen that in this case the alleged right of the Duke to the whale was a delegated one from the Sovereign. We must needs inquire then on what principle the Sovereign is originally invested with that right. The law itself has already been set forth. But Plowdon gives us the reason for it. Says Plowdon, the whale so caught belongs to the King and Queen, “because of its superior excellence.” And by the soundest commentators this has ever been held a cogent argument in such matters.