errupted by unfavorable weather), with the sextant, the repeating
circle of reflection, and the transit instrument, until the latitude and
longitude of the monument and of this first camp were satisfactorily
ascertained, and also the direction of the true meridian from the said
monument established. For this latter purpose several observations
were in the first place made upon the polar star ([Greek: alpha] Ursae
Minoris) when at its greatest eastern diurnal elongation, and the
direction thus obtained was afterwards verified and corrected by
numerous transit observations upon stars passing the meridian at various
altitudes both north and south of the zenith. These were multiplied with
every degree of care, and with the aid of four excellent chronometers,
whose rates were constantly tested, not only by the transit
observations, but also by equal altitudes of the sun in the day, to
correct the time at noon and midnight, and by observed altitudes of east
and west stars for correcting the same at various hours of the night.

The direction of this meridian, as thus established by the commissioner,
was found to vary from the experimental line traced by the surveyors of
1817 by running in the first place to the west of their line, then
crossing it, and afterwards deviating considerably to the east of it.

At the second principal station erected by the party, distant 6 miles
and 3,952 feet north of the first camp, or 7 miles and 3,240 feet north
of the monument, it found itself 60 feet to the west of the line of
1817. This appeared to be the maximum deviation to the west of that
line as near as its trace could be identified, which was only marked by
permanent objects recognized by the party at the termination of each
mile from the monument. Soon after passing this station the line of 1817
was crossed, and the party did not afterwards touch it, but deviated
more and more to the east of it as it progressed north by an irregular
proportion to the distance advanced.

In order to obtain a correct profile or vertical section along the
whole extent of this meridian line, in the hopes of furnishing data for
accurate comparisons of elevations so far as they might be considered
relevant to the subject in dispute between the two Governments, and also
to afford an accurate base of comparison for the barometers along an
extended line which must traverse many ridges that will be objects of
minute exploration for many miles of lateral extent