Another example of a boundary being defined as running parallel to and at a specified distance from an irregular geographical feature is furnished by a part of the boundary between Massachusetts and New Hampshire, which is a line parallel to the Merrimac River, and distant from it 3 miles on the north. In this case, although the distance of the line designated from the one to which it is to be drawn parallel is but 3 miles, and the country between only mildly undulating or hilly, the boundary as now marked on the ground and accepted as an interstate boundary is but a rude approximation to the one originally defined.
These examples, and others that might with propriety be classified as impracticable boundaries, illustrate again the desirability of accurate geographical knowledge, and still more of an adequate appreciation of the difficulties and limitations met with by the surveyor, on the part of those who attend to the real-estate business of nations.
The line of separation between Canada and the United States, as defined by the Treaty of Ghent, 1814, and after several subsequent adjustments, was determined as indicated roughly on the accompanying map. Throughout the greater part of its eastern half it is a river boundary, and in its western half an astronomical boundary.
In 1876 the English Government granted Newfoundland jurisdiction over Labrador, and in letters patent defined that dependency as "all the coast of Labrador, from the entrance of Hudson Straits to a line to be drawn due north and south from Ause Sableu on the said coast to the fifty-second degree of north latitude, and all the islands adjacent to that part of the said coast of Labrador." This line is still unsurveyed. From the fifty-second parallel to the Strait of Belle Isle, a distance of about 40 miles, the boundary is a north-and-south line situated about 7 miles west of the fifty-seventh meridian, as is indicated on the best maps available.
The southern boundary of the United States, as finally determined in 1853 by treaty with Mexico, is, beginning
at the east, a river boundary for some 900 miles, namely, the middle of the Rio Grande, or its deepest channel, when there is more than one, to where the river crosses the parallel of latitude 31° 47'; continuing westward, the line is in part an astronomical and in part an arbitrary boundary to the Pacific.
The nature of the boundaries separating the several provinces of Canada, the various States of the United States and of Mexico, the republics of Central America, etc., are indicated approximately on the accompanying map. These lines when studied on larger-scale maps on which the drainage and relief are also shown reveal many features of interest.
POLITICAL CONTROL
The political subdivisions of North America in 1900 are too well known to require specific description at this time. The long-continued struggles and rivalries that have led to the present subdivision of territory pertain to history, and although full of interest from the point of view of the geographer, cannot be discussed in the present treatise. Among the conspicuous events that might be shown by a series of political maps is the contraction and final disappearance of Spanish and French dominion from the continental mainland. The broad, indefinite territory once belonging to Spain, which in the sixteenth century seemed destined to expand still more and possibly embrace the whole of the two Americas, has been diminished from time to time, until as a result of the recent Spanish-American War her flag no longer waves over any portion of the New World. The French territory, once embracing a large portion of what is now Canada and the United States, is at present represented by the islands Martinique and Guadeloupe with its dependencies, in the West Indies, and the islands Miquelon and St. Pierre, adjacent to the south coast of Newfoundland; in all, comprising about 1,161 square miles. The French have, in addition, certain treaty rights pertaining to fisheries on the northern and western shores of Newfoundland.
Between the two forms of government, monarchical and