I.

In order to the more exact and successful performance of the duties
included under the first of the above heads, the boundary line was
divided by their instructions into three separate portions, one of
which was assigned to each of the commissioners; and while they were
instructed to assemble in a board for the purpose of comparing their
respective surveys, in view of the performance of the duties included
in the second of the above divisions their explorations have been
separately conducted. Each of the commissioners has employed the methods
and course of action most appropriate in his opinion to the successful
fulfillment of his appointed task, and the nature of the surveys
assigned to one of them has been of a character widely different from
those of his colleagues. The commissioners, therefore, while uniting in
a general report of the progress made up to this time in the duties of
their appointment, beg leave to submit, in the form of appendices, the
narrative of their several operations, with so much of the records
of their observations and calculations as they have severally judged
necessary to authenticate the conclusions at which they have arrived.

The progress which has been made in the labors of the commissioners
enables them at this time to lay before you--

1. A description of the physical features of the disputed territory.

2. A comparison of the heights of the line claimed by the United States
with those of the line styled the "axis of maximum elevation" by Messrs.
Featherstonhaugh and Mudge. In laying the latter before you they have,
in order to avoid delay, made use in part of the published results
obtained by those gentlemen, and although they have already detected
errors in their inferences they do not consider that by accepting them
for the moment as the basis of comparison they can be accused of
exhibiting the line claimed by Great Britain in an unfavorable light.

I.--DESCRIPTION OF THE DISPUTED TERRITORY.

The seacoast of the State of Maine is rugged and hilly. The primitive
rocks of which its geological structure is chiefly composed are broken
into ridges which run parallel to the great streams, and therefore in a
direction from north to south. These ridges terminate in an irregular
line, which to the east of the Penobscot may be identified nearly with
the military road to Houlton. From the northern summit of these ridges
an extensive view of the disputed territory can in many places