have been surveyed by various organizations on such a scale and in such a
manner that the work has been accepted as sufficient for the purposes of
the Survey.

Much other work has been done, but not with sufficient refinement and
accuracy to be of present value, though such work subserved its purpose in
its time. An examination of the map will show that the triangulation of
the various organizations is already largely in advance of the topography.
The map of the United States will be a great atlas divided into sheets as
above indicated. In all of those areas where the survey is on a scale of
1-250,000, a page of the atlas will present an area of one degree in
longitude and one degree in latitude. Where the scale is 1-125,000, a page
of the atlas-sheet will represent one-fourth of a degree. Where the scale
is 1-62,500, the atlas-sheet will represent one-sixteenth of a degree. The
degree sheet will be designated by two numbers--one representing latitude,
the other longitude. Where the sheets represent fractional degrees, they
will be labeled with the same numbers, with the addition of the
description of the proper fractional part.

The organization, as at present established, executing this work, is as
follows: First, an astronomic and computing division, the officers of
which are engaged in determining the geographic coordinates of certain
primary points. Second, a triangulation corps engaged in extending a
system of triangulation over various portions of the country from measured
base-lines. Third, a topographic corps, organized into twenty-seven
parties, scattered over various portions of the United States. Such, in
brief outline, is the plan for the map of the United States, and the
organization by which it is to be made. Mr. Henry Gannett is the Chief
Geographer.