ooode.] THE LINE WEST OF THE SUMMIT. 59 
Range, on and near the boundary, perpetual snow covers many of the peaks, 
whose northern gorges are filled up with immense glaciers. The timber on the 
western slope of the Cascade Mountains is dense, being a heavy growth of pine 
and fir that in many places stands over a fallen forest not yet decayed. This is 
the character of the country as far eastward as the valley of the Similkameen 
River, one of the tributaries of the Columbia. Here the timber becomes more 
open and surveying operations less difficult. 
After passing the Okinokane River, which is the lowest line of the great valley 
between the Cascade and the Rocky Mountains, the country again becomes rough 
and the timber more dense, but less so than the western slope of the Cascade 
Mountains. 
It being impossible to follow the forty-ninth parallel continuously, the line of 
survey was carried over the nearest practicable route for a pack trail, connecting 
each astronomical station, making a total length of line of survey of about 800 
miles. Astronomical stations were established by parties of the joint commission 
at almost every accessible point from which the boundary line is ascertained, and 
marked by a vista across all valleys and trails, where rough stone monuments 
were erected over posts buried in the ground to indicate the exact line. 
The reconnoissance work extends over an area of about ;W,000 square miles. 
Within this space the barometrical heights of over 800 points have been obtained. 
A magnetic survey, extending over a range of 30° 20 in latitude and 4° in longi- 
tude, with the necessary observations of the magnetic elements of the astronom- 
ical stations, was also made. 
The entire length of the land boundary line is over 9° in longitude, or about 410 
miles, and the length of the route traveled in surveying it is double that distance. 
Trails had to be opened for three-fourths of the distance traveled, involving great 
labor in cutting, grading, and bridging to make the route practicable for pack- 
mule transportation. The water courses were numerous and rapid, rendering the 
fords frequent and dangerous, and a slight rise of many of the streams would have 
made them impassable but for the timely precaution of building bridges at small 
streams and ferryboats at the river crossings. Many of the trails opened are now 
traveled routes to the mines then and since discovered, which are rapidly develop- 
ing that section of the country, where almost every valley of any extent affords 
facilities for agricultural pursuits. 
In collating the results of the survey reports upon the geology, botany, and 
natural history of the country reconnoitered were prepared and complete maps, 
on a large scale, made of the entire boundary and the adjacent country. A gen- 
eral map has also been made, showing the extent of the country traversed. And 
to facilitate the survey of the public lands photographic duplicates of the detailed 
sheets, showing each monument on the boundary line, with its geographical posi- 
tion, were furnished to the General Land Office. Photographic duplicates of the 
detailed sheets of the water boundary have also been made and furnished the 
Department of State in illustration of the question of the boundary channel. 
Copies of the maps referred to in Mr. Campbell's reports are in 
existence. The boundary-line maps are in 14 sheets, with the title, 
Detailed Maps of the Northwest Boundary, from Point Roberts to the 
Rocky Mountains, between the United States and the British Posses- 
sions, under the treaty of June 15, 1846, showing monuments, cuts, 
and other marks. The scale of the maps is 1:60,000, and the topog- 
raphy is shown in hachures. The general map referred to is in con- 
tours and apparently on the same scale as the detailed map*. 
From an inspection of the detailed map it appears that there are 
