the northern extremity of the long range of hills,
starting just east of York. The wagon roads pass through numerous
cuts--west of Twin Hills, northern end of Sandy Ridge, southeastern
end of Long Ridge, and so on. The small T's along the railroad and
some of the wagon roads, indicate telegraph or telephone lines.

The conventional sign for a bridge is shown where the railroad crosses
Sandy Creek on a trestle. Other bridges are shown at the points the
wagon roads cross this creek. Houses or buildings are shown in Oxford,
Salem, York and Boling. They are also shown in the case of a number of
farms represented--Barton farm, Wells farm, Mason's, Brown's, Baker's
and others. The houses shown in solid black are substantial structures
of brick or stone; the buildings indicated by rectangular outlines are
"out buildings," barns, sheds, etc.

Plates I and II give the Conventional Signs used on military maps and
they should be thoroughly learned.

[Illustration: Plate I]

[Illustration: Plate II]

In hasty sketching, in order to save time, instead of using the
regulation Conventional Signs, very often simply the outline of the
object, such as a wood, a vineyard, a lake, etc., is indicated, with
the name of the object written within the outline, thus:

[Illustration: Fig. 19]

Such means are used very frequently in rapid sketching, on account of
the time that they save.

By reference to the map of Fort Leavenworth, the meaning of all its
symbols is at once evident from the names printed thereon; for
example, that of a city, woods, roads, streams, railroad, etc.; where
no Conventional Sign is used on any area, it is to be understood that
any growths thereon are not high enough to furnish any cover. As an
exercise, pick out from the map the following conventional signs:
Unimproved road, cemetery, railroad track, hedge, wire fence, orchard,
streams, lake. The numbers on the various road crossings have no
equivalent on the ground, but are placed on the maps to facilitate
description of routes, etc. Often the numbers at road crossings on
other maps denote the elevation of these points.

Visibility

=1875.= The problem of visibility is based on the relations of
contours and map distances previously discussed, and includes such
matters as the determination of whether a point can or can not be seen
from another; whether a certain line of march is concealed from the
enemy; whether a particular area is seen from a given poi