peace: the latter are temporarily safeguarded by dynastic alliances. But in both groups lie critical Frontier issues of the future.
I now proceed to the examination of the commoner forms of Artificial Frontiers in use among modern States. These are three in number: (1) what may be described as the pure astronomical Frontier, following a parallel of latitude or a meridian of longitude; (2) a mathematical line connecting two points, the astronomical coordinates of which are specified; and (3) a Frontier defined by reference to some existing and, as a rule, artificial feature or condition. Their common characteristic is that they are, as a rule, adopted for purposes of political convenience, that they are indifferent to physical or ethnological features, and that they are applied in new countries where the rights of communities or tribes have not been stereotyped, and where it is possible to deal in a rough and ready manner with unexplored and often uninhabited tracks. They are rarely found in Europe, or even in Asia, where either long settlement or conflict has, as a rule, resulted in boundaries of another type.
(1) The best known illustration of the astronomical line is the Frontier between Canada and the United States, which from the Lake of the Woods follows the 49th parallel of latitude to the Pacific coast, a distance of 1,800 miles. This line well illustrates both the strength and the weakness of the system. As a conventional line through unknown territories it has answered its purpose. But its demarcation on the spot was so laborious and protracted that, fifty years after the conclusion of the Treaty which created it, the joint surveyors were still at work, clearing a strip 100 yards wide