The noi'tliern boundary of this country is unarked by stonecairns, iroo pilliirs, wooden piliars, enrtli ïnoinuls aiul tlmber posts. A stonecairn is 7i feet by 8 feet, ui earth mouiid 7 feet by 14 fëet, ui iron pillar 8 feet higli, 8 inches square at the bottom and 4 inches at the top, tiniber posts 5 feet high and 8 inches square. There are 382 of these ruarks betwecn the Lake of the "Woods and tke base of the Kocky Moimtains. That portion of the boundary which lies east and west of the lied Iliver Valley is marked Jjy cast iron pilláis at even inile intervals. The Britisti place one every two miles and the United States one between each liritish post. ()ur piUars or markers were made in Detroit Mich. They are hollow iron castings, three-eightlis of au inch in thickness, in the form of a truncated pyramid, 7 feet high, 8 inches square at the bottom and 4 inches at the top, as bef ore stated. They have at the top a solid pyrainid cap, and at the bottom an octagonal (lange one inch in thickness. Upon the opposite face are cast in letters two inches high the Inacriptioft: "Convention of London" and "October20, 1818." The inscriptious begin about four feet si inchee above tlie liase, and read upvrards. The interiora of the posts are filletl with well-seasosed cednr posts, sawed to fit, and securely spiked tlirough spike lióles cast in the pilláis for the purposc. The average weight of eacb pillar when eompleted iseightyíive pounds. The pillará are all set tour feet in the ground, with their inscription facas to the norlli and south, and the earth is wéU settled and stamped about thein. For the wooden posts well-seasoned logs are selected, and the portion above the ground painted red, to prevent swelling and shrinking. These posts do very well, but tlie Indians cut them down for luel, and nothing but iron lust very long. Wbere the lines crosses lakes, monunients of stone have been built, the bases being in some places eighteen feet imder water and the tops projectlng eightfeet above tlie lake's Burface at high water mark. Jn forests the line is niaiked bj feil ing the timber a rod wide and clearing a way the iniderbrush. The work of cutting tlirough the timered swainps was very great, but it luis been well done and the bounilury distinctly marked by the Comrnisúoners the whole distance from Micliitr;m to Alaska.