At the time when America was discovered, the law of nations was altogether unsettled. More than a century elapsed before Grotius attempted to lay its foundation on Natural Law and the moral precepts of Christianity; and, when sustaining it by precedents, he was compelled to recur to Rome and Greece. It was in reality a new case, to which no ancient precedents could apply,[2] for which some new rules must be adopted. Gradually, some general principles were admitted, never universally, in their nature vague and often conflicting. For instance, discovery varies, from the simple ascertaining of the continuity of land, to a minute exploration of its various harbors, rivers, &c.; and the rights derived from it may vary accordingly, and may occasionally be claimed to the same district by different nations. There is no precise rule for regulating the time after which the neglect to occupy would nullify the right of prior discovery; nor for defining the extent of coast beyond the spot discovered to which the discoverer may be entitled, or how far inland his claim extends. The principle most generally admitted was, that, in case of a river, the right extended to the whole country drained by that river and its tributaries. Even this was not universally conceded. This right might be affected by a simultaneous or prior discovery and occupancy of some of the sources of such river by another party; or it might conflict with a general claim of contiguity. This last claim, when extending beyond the sources of rivers discovered and occupied, is vague and undefined: though it would seem that it cannot exceed in breadth that of the territory on the coast originally discovered and occupied. A few examples will show the uncertainty resulting from those various claims, when they conflicted with each other. The old British charters extending from sea to sea have already been mentioned. They were founded, beyond the sources of the rivers emptying into the Atlantic, on no other principle than that of contiguity or continuity. The grant in 1621 of Nova Scotia, by James the First, is bounded on the north by the river St. Lawrence, though Cartier had more than eighty-five years before discovered the mouth of that river and ascended it as high up as the present site of Montreal, and the French under Champlain had several years before 1621 been settled at Quebec. But there is another case more important, and still more in point.