monument of the conical bronze type at a point that had originally been selected as the site for Monument 45, but at which a monument had not heretofore been set. This new monument was numbered 45, and the monument originally set / mile to the westward and numbered 45 was renumbered 44-A. At Blaine, Washington, they set 4 new monuments to mark the boundary at the crossing of the Pacific Highway. Two of these four were set on the boundary, one on each side of the roadway passing the west side of the Peace Portal, and two were set on the boundary, one on each side of the roadway passing the east side of the Peace Portal. These monuments were of the ornamental concrete type used to mark highway crossings. They were numbered, from west to east, 5-A, 5-B, 5-C, and 5-D.

The field work of 1930 to 1936, inclusive, covered the entire section of the boundary west of the Rocky Mountains. During this 7-year period all of the boundary monuments were inspected and many repairs made; a large portion of the vista was recut; new monuments were set; and the work of determining the geodetic positions of all of the monuments was completed, making it now possible to describe the entire boundary from Georgia Strait to the Northwesternmost Point of Lake of the Woods in terms of geodetic positions as other sections of the boundary have been described in the reports of the Commissioners.

All of the field work subsequent to 1925, described in the foregoing paragraphs, has been reported upon in detail in the several annual joint reports of the Commissioners upon maintenance work submitted by them in duplicate to their respective Governments in accordance with the provisions of article IV of the treaty of 1925

THE PEACE PORTAL; ON THE INTERNATIONAL BOUNDARY AT THE CROSSING OF THE PACIFIC HIGHWAY ON THE EAST SHORE OF BOUNDARY BAY AT THE NORTH LIMITS OF BLAINE, WASHINGTON; ERECTED BY THE PACIFIC HIGHWAY ASSOCIATION UNDER THE DIRECTION OF THE LATE SAMUEL W. HILL. THE MONUMENT IS IN COMMEMORATION OF THE TREATY OF GHENT, SIGNED DECEMBER 24, 1814, SINCE WHICH TIME PEACE HAS BEEN KEPT BETWEEN THE TWO NATIONS WITHOUT ARMED FORCES OR FORTIFICATIONS ALONG THEIR COMMON BORDER. THE MONUMENT WAS BEGUN IN 1914 AND WAS COMPLETED AND DEDICATED IN 1921

FIELD AND OFFICE METHODS AND RESULTS

HORIZONTAL CONTROL

The horizontal control for the topographic surveys and for the determination of the geographic positions of the monuments marking the boundary line from the shore of Georgia Strait to the Northwesternmost Point of Lake of the Woods consists of a belt of major triangulation supplemented by schemes of minor triangulation and traverse. This belt of triangulation and traverse is controlled by the arc of first-order triangulation and traverse of the United States Coast and Geodetic Survey and the Geodetic Survey of Canada extending along the International Boundary from the Pacific Ocean to Lake Superior.

The general plan of control is shown on the 30 triangulation sketches on pages 428 to 457 of appendix V.

The geographic positions and descriptions of the triangulation and traverse stations are listed in appendix V pages 254 to 427.

The first-order control is an arc of the western net of first-order triangulation, readjusted by the United States Coast and Geodetic Survey to establish the North American geodetic datum of 1927.

The major triangulation of the boundary survey is an almost continuous belt of triangulation paralleling or straddling the boundary from Point Roberts to Lake of the Woods. It has been tied in, frequently, to the stations of the first-order control so as to permit of a rigid adjustment therein. The tie points to the firstorder triangulation are plainly indicated as such in the lists of geodetic positions and on the triangulation sketches to be found in appendix V.

Inside of the major scheme, and controlled by it, are the minor schemes of triangulation and traverse used to locate the boundary monuments.

West of the summit of the Rocky Mountains the extremely tall and heavy growth of forests, the deep valleys, and the precipitous mountain ranges often made it extremely difficult to locate the monuments by triangulation. Consequently when the line was first reestablished and remonumented in 1903 to 1907 many of the monuments were omitted from the triangulation scheme. The distances between these monuments were determined at that time only by chaining or by stadia measurements of a comparatively low order of accuracy. Since that time the geographic positions of all these monuments have been determined by triangulation or by accurate traverse. This work has been done in conjunction with maintenance work under the treaty of 1925 and was completed in 1936.

The horizontal control of the Lake of the Woods region consists of an auxiliary scheme of first-order triangulation, tied to the first-order traverse at Warroad, Minnesota, extending over the southern part of Lake of the Woods; a minor scheme

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of triangulation extending from this first-order scheme to Northwest Angle Inlet; and an invar tape traverse run along the meridian boundary from Northwest Angle Inlet to Buffalo Bay where it completes a circuit by a tie to the first-order triangulation.* The geographic positions of the monuments on the meridian line are determined by the invar tape traverse.

The methods used both in the field work and in the office computations of the horizontal control follow in general the standardized methods of the United States Coast and Geodetic Survey and the Geodetic Survey of Canada for work of comparable character.

MONUMENTS AND MONUMENTING

The International Boundary from the Gulf of Georgia (Georgia Strait) to the Northwesternmost Point of Lake of the Woods is marked by 959 monuments set on the boundary line, 2 reference monuments referencing the Northwesternmost Point of Lake of the Woods, and 4 range marks ranging the boundary across Boundary Bay between Monuments 4 and 5. The monuments have been interspaced so as to make the demarcation of the line as effective as possible. They are placed on heights of land, at crossings of prominent streams, at convenient intervals on the level plains, and at crossings of important international highways.

Wherever possible and it is so in the majority of instances the monuments are so placed as to be consecutively intervisible. Nine hundred and twenty-six of the boundary monuments bear the consecutive numbers from 0 to 925, Monument 0 being the initial monument on the eastern shore of Georgia Strait and Monument 925 being the most northern monument on the meridian boundary and the first one south of the Northwesternmost Point of Lake of the Woods. The other 33 boundary monuments established subsequent to 1907 are designated by letters combined with the number of the consecutively numbered monument just preceding, as for example, 116-A, 116-B.

TYPES OF MONUMENTS

The monuments which mark and reference the boundary are of the following 11 types:

1. General type of cast-iron monument made in 1872-76 and in 1908-13. (Fig. 1.)

2. General type of aluminum-bronze monument made and set in 1904–9. (Fig. 2.)

3. General type of concrete monument for marking highway crossings. (Fig. 3.)

4. Special granite monument erected in 1861.

5. Special concrete monument with bronze post.

6. Shore range-mark tower. (Fig. 6.)

(Fig. 4.)
(Fig. 5.)

*For complete data, horizontal control of the Lake of the Woods region, see the Commissioners' Joint Report upon the Survey and Demarcation of the Boundary between the United States and Canada from the Northwesternmost Point of Lake of the Woods to Lake Superior, 1931, appendix V, and accompanying triangulation sketches.