APPENDIX E LXXIIT 
tended eastward parallel to the 45th parallel of latitude. Reconnais- 
sance has been nearly completed over this district, which is a difficult 
one in that respect, the elevations being small, and largely covered with 
trees. This necessitates high observing stations to get proper length of 
sides (15 to 20 miles). Many of these scaffoldings have been erected, 
and that part of the work is being actively pushed. It is intended to 
begin the observing in a short time. 
7. Boundary Surveys. 
These comprise the surveys of the boundary between Canada and 
the United States under certain conventions and executive agreements. 
The boundary surveys are four in number, the survey of the 141st 
meridian, under the Convention of 1906; the survey of the boundary line 
from the southermost point of Prince of Wales Island and the 141st 
meridian under the Award of the Tribunal of 1903, and the supplement- 
ary agreement of 1905; the re-survey of the boundary line from Lake 
Superior to the Pacific Ocean under agreement made in 1902; and the 
re-survey of the boundary line from Richelieu River to the source of the 
St. Croix River, under agreement of 1906. The line from Richelieu 
River to the St. Lawrence was re-surveyed and re-marked in 1902 and 
1903 under an agreement with the State of New York, with the con- 
currence of the United States Government. 
It will be observed that the first two divisions of the boundary 
surveys are new work, the demarcation of boundary lines, which have 
not previously been marked on the ground. The last two consist in 
the re-survey of previously marked lines, and renewal of the monuments 
where necessary. The third section, from Lake Superior to the Pacific 
includes, however, some portions never before marked, viz: the part 
between Lake Superior and Lake of the Woods and certain portions of 
the southern boundary of British Columbia. 
The work of survey and demarcation in all cases comprises the 
accurate production of the line between determined points, the cutting 
of vistas through the timber, triangulation along the line for linear 
distance, topographical survey for a certain distance on each side of the 
line, levelling, check astronomical observations, ete., and the placing of 
monuments. 
In the case of the 141st meridian the convention required its deter- 
mination by the telegraphic longitude method at a convenient place, and 
the production of the line therefrom north and south. The telegraphic 
determination was made last summer at the crossing of the Yukon 
River ; by combination of the best available data the observing point had 
been chosen at what was thought the most probable position of the 
meridian of 141°W. When the observations were worked out the dis- 
