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Sta. 16 + 17.1, west track, is another cross-over, which we
call track H. The curves are both 9 30', described in
opposite directions, as in the preceding case.

Starting at Sta. 5 of the S. & B. R. R., which is directly
over the center line of the towpath of the C. & O. canal,
the bearing of which is N 54 30' E, we measure north-
eastward along the center line of the towpath 70G ft. to the
P. C. of a 12 R. for 12. Produce the back and forward
tangents of this curve until they intersect the borders of
the plat. The towpath is 12 ft. wide and the canal 40 ft.
wide. The canal makes the same curve as the towpath, the
arcs being struck from the common center. The student
will draw the boundaries of the canal and towpath in ink,
but need not ink in the center line of the towpath. The
north abutment of the Main St. canal and river bridge is
4 ft. from the boundary of the canal. At 443 ft. from our
starting point on the towpath is the west end of a canal
dock, which consists of a widening of the canal in which
boats are moored while their cargoes are being dis-
charged. This dock is 240 ft. long and 20 ft. wide, provi-
ding berths for four boats. At 120 feet from the west end of
the dock is the west end of a coal chute, the south side of
which is parallel to and 20 ft. from the dock. The coal
chute is 40 by 200 ft. The railroad bridge over the canal is
30ft. wide. The south abutment is placed 12 ft. and the
north abutment 6 ft. from the canal, both abutments being
parallel to the canal. The outer faces of the wing walls of
these abutments are parallel to and 10 ft. from the center
line of the nearest track.



MAPPING. 799

PLATE, TITLE: MAP OF A VILLAGE.

1384. This plate represents a topographical map of a
village. In making a survey of this description the engineer
will select for a starting point some well-defined landmark ;
but as there are a score of points to choose from, the choice
will depend upon the judgment of the engineer. The in-
tersection of the center lines of two highways or the head
block of a railroad switch are excellent points from which to
commence a survey. The center lines of highways and
railroads are the base lines from which the minor details,
such as houses and other buildings are located. The quickest
and best method of locating a building is to set a temporary
plug on the base line near the building. Set up the transit
at this point and measure the angles between the base line
and two consecutive angles of the building, measuring the
distances from the plug to the angles of the building. These
angles and distances will locate one side of the building. A
small free-hand sketch is then made, giving the base line,
the station of the plug, or its distance from some known
point, and the angles and distances to the side of the build-
ing. The remaining sides of the building are added to the
sketch and their several lengths measured in consecutive
order and marked on the sketch. These notes are quickly
made and as quickly platted.

Sketches are of the greatest value in taking topographical
notes. They can be made in less than half the time re-
quired for a full description, and are always more intelligi-
ble to the draftsman. Each surveyor has his individual
methods, both in order of work and form of notes, and
often one will consume twice as much time as another in
performing the same work; but expedition is of no value if
had at the cost of accuracy.

In this map all the conventional signs suited to an area of'
such magnitude are employed. The student will draw the
map to a scale of 200 feet to the inch. The magnetic merid-
ian is parallel to the right and left borders of the plate,
the north point being at the top of the map. The center
lines of the highways are given, together with their mag-



800 MAPPING.

netic bearings, widths, and distances between the angles
made by the center line. The center line of the railroad is
represented by a heavy, full line, and the boundaries of the
right of way, which is 100 feet in width, are represented by
light full lines. The magnetic bearings of the tangents are
given and the stations of the points of curve and tangent
from which the lengths of the tangents are found by sub-
tracting the station of the P. T. of one curve from the
P. C. of the succeeding curve. The curves, instead of
being run in from intersections of tangents, are platted as
follows :

The location of the first tangent in the map being given
by references to the boundary lines of the map, and the
P. C. of the first curve denoted by its station, a perpendicu-
lar is erected to the given tangent, and upon it the length
of the radius of the required curve is laid off to the given
scale. Then, from the given center the curve is struck with
a compass, being careful that the arc so struck shall contain
as many degrees as the central angle of the curve, the
central angle of the curve being laid off with a protractor.
The intersection of the second radius with the arc will be
the P. T. of the following tangent. A perpendicular is then
erected to the second radius and tangent to the arc at the
given intersection. The P. C. of the next curve being given,
its length is readily found by subtraction. The borders of
the lake are located by offsets.

The student is not expected to exactly duplicate the
topography, but give the same general effect. All bound-
aries whose magnetic bearings are given and the location of
all buildings he must faithfully repeat in his drawing.

1385. Starting at the northwest corner K of the map
we measure eastward along the north boundary 700 ft. to
Z,, the center of the S. & L. R. R., the bearing of which at
that point is S 7 45' E. At 310 feet from this point is the
P. C. of an 8 curve R., which we call Sta. 40 + 60. The
central angle of this curve is 25, and its length 312.5 ft
The station of the P. T. we find by adding the length of the



MAPPING. 801

curve to the station of the P. C., giving 43 + 72.5 for the
P. T. of the curve. The bearing of the forward tangent is
S 17 15' W and its length 400 ft., making the station of
the next P. C. 47 + 72.5. This curve is 9 R. and its central
angle is 15. It's length is, therefore, 166.7 ft., and the sta-
tion of the P. T. 49+ 39.2. The bearing of the forward
tangent is S 32 15' W, found by adding the central angle
of 15 to the bearing of the preceding tangent. The length
of the forward tangent is 610 ft. to Sta. 55 + 49.2, which is
the P. C. of a 6 curve L. The curve is continued to the
south boundary of the map.

The switch extending to. the ice houses along the shore of
the lake is located as follows:

Scale off from the northwest corner K of the map, along
the north boundary 790 ft., eastward to the point M. From
this point as a center, lay off with a protractor to the right
of the north boundary an angle of 32 30'. The bearing of
this line is S 57 30' E. Scale 47 ft. on this line from the
point in the boundary where the angle is turned. This will
locate the P. C. of a 16 curve R., the station of which is
3 + 04.7. The central angle of this curve is 62 05', and the
station at the P. T. 6 + 92.7. The bearing of the forward
tangent is S 4 35' W. The next curve is 10 R. Its P. C.
is at Sta. 10+93.7, and its central angle is 9 40', which
brings the P. T. at Sta. 11 + 89.4. The bearing of the for-
ward tangent is S 14 15' W. The next curve is also 10 R.
Its P. C. is at Sta. 15 + 49.4, and its central angle 27 30',
which brings the P. T. at Sta. 18 + 24.4. The bearing of
the forward tangent is S 41 45' W. The last curve is 10
L. Its P. C. is at Sta. 24 + 24.4, and its central angle is
27 10', which brings the end of the line at Sta. 26 + 96.1.

With a protractor lay off from the P. C. of the 16 curve
of the ice switch, a central angle of 18. Draw a radius in-
eluding this angle and at its extremity draw a tangent to
the curve, with bearing of S 39 30' E. This point of tan-
gent is the starting point of a switch leading to a coal chute.
This point we call Sta. 0. At Sta. + 65 of this track is the
P. C. of an 18 curve R. for 36, bringing the P. T. at Sta,



802 MAPPING.

2 -f- 05. At this point the track enters a coal chute 50 ft. long
by 30 ft. wide. The center line of the track is parallel to
the sides of the chute and spaced 7 ft. from the west side.
At 120 ft. from the starting point of the S. & L. R. R. is the
north end of platform of a railroad station, and at 21 ft. from
that point is the south end of the platform. The edge of this
platform is spaced 6 ft. from the center line of the railroad
track. The platform is 46 ft. in width at the north end and
50 ft. in width at the south end. The center line of a road
40 ft. wide commences at the middle point of the south end
of the railroad station platform, and extends in the direc-
tion S 48 30' E 500 ft., where it intersects with the center
line of the Scranton turnpike, the bearing of which is S 21
30' W. Call this point of intersection A.

Starting from intersection A, the traverse of the center
line of the turnpike is as follows: S 21 30' W 310 ft.;
thence, S 58 30' E 80 ft. to the west end of a bridge 20 ft.
wide; thence, by same course 40 ft. to east end of bridge;
thence, by same course 80 ft. to an intersection with center
line of Andrews lane. Call this point of intersection B.
Thence, S 11 30' W 300 ft. to intersection with center line
of Waverly road. Call this point of intersection C. Thence,
by same course 300 ft. ; thence, S 8 30' E 250 ft. ; thence,
S 27 E 345 ft. to north end of a stone bridge 20 ft. wide ;
thence, by same course 30 ft. to south end of stone bridge;
thence, by same course 125 ft. to an intersection with the
center line of Newton road, the direction of which is N 63
E and width 40 ft. Call this intersection point D. From
intersection D the turnpike extends in the direction N 83 E
400 ft., thence, S 76 E 325 ft.; thence, S 46 E to the
south boundary of the map. The width of this turnpike is
50ft.

Next we measure from the northwest corner K of the
map, southward along the west boundary 344 ft. to the cen-
ter N of the Benton road. From thence we measure along
the center line of the road, N 80 15' E 356 ft. ; thence,
S 69 45' E 350 ft. ; thence, S 89 45' E 45 ft. to west end of
a culvert 20 ft. in width ; thence, by same course, 50 ft. to



MAPPING. 803

east end of culvert; thence, by same course, crossing the ice
switch and road leading to the railroad station and continu-
ing to an intersection with the Scranton turnpike, which is
the terminus of the Benton road. Call this point of inter-
section E.

Starting at intersection C, we follow the center line of the
Waverly road as follows: S 55 15' E 197 ft. to its intersec-
tion with the center line of Lenox lane. This point of in-
tersection we call F. Thence, N 74 45' E 500 ft. ; thence,
S 85 15' E, intersecting the old Scranton and Montrose
turnpike and extending by the same course to the east
boundary of the map.

Returning to the point /*, the intersection of the center
line of the Waverly road with Lenox lane, we prolong
the line C F from F, a distance of 290 ft. This forms the
center line of Lenox lane, and intersects with the center line
of Henderson lane. These intersecting center lines form
an angle of 90 with each other, making the course of
Henderson lane N 34 45' E. Produce the center line of
this lane in both directions, intersecting on the south with
the Scranton turnpike, and on the north with the Waverly
road. The widths of the Waverly road and Lenox and
Henderson lanes are each 40 ft. Commencing at the point
B, where the Scranton turnpike intersects the center line of
Andrews lane, we follow the center line of that lane in the
direction N 31 30' E 300 ft. to an intersection with the cen-
ter line of a private lane leading in the direction S 85 30' E
200 ft., where it turns at right angles, 40 ft. to the right
and 75 ft. to the left. Continuing along the center line of
Andrews lane by the same course 100 ft., we change the
direction, running N 11 30' E, intersecting with Hall road.
The width of Andrews lane is 30 ft.

Starting from the southeast corner O of the map, we
measure westward along the south boundary 320 ft. to the
center P of the old Scranton and Montrose turnpike. From
this point we follow the center line of the turnpike as fol-
lows: N 27 45' W 440 ft.; thence, N 7 45' W 330 ft.;
thence, N 2 15' E 1,280 ft., intersecting the Waverly and Hall



804 MAPPING.

roads. The latter intersection makes the eastern limit of
Hall road. Thence, N 5 45' W to the north boundary of
the map. The width of this turnpike is 50 ft. Returning
to point , the terminus of the Benton and Hall roads, we
follow the center line of Hall road S 89 45' E 1G5 ft. to the
west end of a bridge 20 ft. wide; thence, by same course,
30 ft. to east end of bridge; thence, by same course, 400
ft. to an intersection with the center line of Prospect road,
which extends in the direction N 40 15' E to the north
boundary of the map. Call this point of intersection G.
From the point G the center line of Hall road extends in
the same direction, viz., S 89 45' E to its intersection with
the center line of the old Scranton and Montrose turnpike.
Call this intersection point H. The widths of the Hall and
Prospect roads are 40 feet.

The right of way of the S. & L. R. R. is 100 ft. in width,
50 ft. each side of the center line, excepting at the station,
where the railroad company's property extends in width 100
ft. on the east side from the center line of the track, and in
length from the north boundary of the map to the highway.
On the west it extends in width 200 ft. from the center line
of the track and in length from the north boundary of the
map to the Benton road. At a point 390 feet from Sta.
43+ 72.5 of the main track, as measured on the west right
of way boundary, is the end of the boundary line between
lands of James Henderson and John Andrews, the bearing
of which is S 57 45' E. This boundary extends to the west
boundary of the map. At a point in the center of Hall
road, 10 feet west of intersection G, is a corner at the
schoolhouse lot which fronts 100 feet on Hall road, and 220
feet in depth, as measured from the center line of the road,
the sides being at right angles to the center line of the road.
All property lines bounding on or intersecting highways follow
or extend to the center line of tlie highway. Immediately
adjoining the schoolhouse lot on the west is the lot of John
Stark, with front of 200 ft. and depth of 220 ft. A point
300 ft. east of intersection G, as measured on the center
line of Hall road, is a corner of lot of F. Swartz. This



MAPPING. 805.

boundary is at right angles to the center line of Hall road
and extends to the center of Prospect road. The other
boundaries of the lot are marked by the center lines of the
roads upon which the lot fronts. At a point 300 ft. south
of intersection H, as measured on the center line of the old
turnpike, is a corner of lot belonging to John Edwards.
The sides of the lot are at right angles to the center line of
the turnpike and the ends parallel. The lot fronts 300 ft.
on the turnpike and has a depth of 425 ft. The south
boundary of this lot forms a part of the north boundary of a
lot belonging to Jane Gregory. A line joining the south-
west corner of John Edwards's lot with the northeast corner
of Henry Watson's lot completes the north boundary of the
Gregory lot. The bearing of this line is N 87 10' E. The
west boundary has a bearing of N 4 45' E, and extends to
the center line of Waverly road, with which it forms an
angle of 90. The south and east boundaries of the lot are
formed by the center line of the Waverly road and the old
turnpike, the courses of which are already given. The
point of intersection of the center line of the Waverly road
with the old turnpike is a corner of lot belonging to A.
Atherton. The north boundary extends along the center
line of Waverly road 425 feet; thence, at right angles to
that road, S 4 45' W 420 ft. ; thence, on a line parallel to
the Waverly road, to the center of the old turnpike. The
west boundary is formed by the center line of the turnpike.
The west boundary of lot belonging to Jane Gregory
forms the east boundary of lot belonging to Henry Watson,
which has a frontage of 150 feet and a depth of 220 feet.
The west boundary of Henry Watson's lot forms the east
boundary of lot belonging to James Lenox, and extends
N 4 45' E 220 from the center of the Waverly road.
Thence, N 85 15' W to the center of the Scranton turn- 1
pike. The remaining boundaries of the Lenox lot are
formed by the center lines of the adjoining highways. By
prolonging the* boundary between Henry Watson and James
Lenox northward 275 feet, we form the east boundary of
John Andrews's lot. The same line prolonged to the center



806 MAPPING.

of Hall road forms the east boundary of Clayton Andrews's
lot. The boundary between lots of Johr^ and Clayton
Andrews is formed by the center line of the lane, and that
center line produced to the east boundary of the lots. The
remaining boundaries of these lots are. formed by the center
lines of the adjacent highways. At 210 feet from inter-
section C, as measured on the center line of the Waverly
road and Lenox lane, is the northwest corner of a lot belong-
ing to the Lenox estate. This lot has a front of 60 feet and
a depth of 180 feet, the sides being at right angles to the
center line of Lenox lane.

All buildings the student will locate by eye, giving to
them the same shape and proportions as shown in the plate.
Shade trees are spaced 50 feet, their rows being placed
10 feet inside the road boundaries. Fruit trees are spaced
40 and 30 feet. The usual conventional signs are employed
to represent the topography. As grass and cereals are much
alike in appearance, the conventional sign for grass may be
varied so as to represent them all and so give variety to the
drawing. A part of the lot belonging to James Henderson
is occupied by a vineyard, which is represented by rect-
angles enclosed in wavy outlines. These signs might also
be used to represent small fruits growing on trellises. All
other conventional signs employed have been previously
described, with appropriate illustrations.

1 386. Colored Topography. All conventional signs
so far described are made with a pen. Often, where sur-
veys cover extensive areas, the labor and time for pen work
can not be spared, and colors applied with a brush are used
instead. With a skilful hand, work of this character may
be rapid and very effective. But three colors besides India
ink are required; gamboge (yellow), indigo (blue), and lake
(scarlet). The colors used in the drafting room are of
two kinds, viz., dry and moist. Dry colors are sold in the
form of rectangular cakes, wrapped in tin foil'. Moist colors
are packed in small dishes of porcelain. These dishes are
rectangular in form, open at top. The surface of the paint



MAPPING. 807

is covered with wax and the entire dish wrapped in tinfoil.
In using, rub the cake of color with a moistened brush
which will take up sufficient color. Dilute the color in
water to the proper tint, which should always be light and
delicate. To cover a surface with a uniform tint, use a
camel's hair or sable brush. Use a separate brush for each
tint and provide plenty of dishes for the various colors.
Confusion in the use of brushes is sure to spoil a tint. For
large masses of the same tint, a large brush should be used,
but for vegetation or small details, small brushes are indis-
pensable. Avoid heavy strokes. Light and rapid strokes
produce smooth and pleasing effects. The map should be
pinned to a light drawing board, so that it may readily be
inclined at an angle. Keep the brush well filled with color
and begin at the top of the surface, inclining the board
towards you. If the outline is very irregular, moisten
the edge with water. Apply the tint the full length
of the surface and continue it down the surface, never
allowing the edge to dry, which is the secret of a smooth
tint.

Woods are commonly colored yellow ; grass land, green,
made of gamboge and indigo; cultivated land, brown, made
of lake, gamboge, and India ink; brushwood, marbled green
and yellow; vineyards, purple, made of lake and indigo;
lakes and rivers, of light blue, with a darker tint at the
shore line; seas, dark blue, with a little yellow added;
marshes, the water blue, with patches of green applied hori-
zontally, and roads, dark brown. Woods may be made very
effective by drawing the trees, coloring the angle towards
the light (the upper left hand) with a touch of yellow, and
indigo on the opposite, or lower, right-hand side.

Skill and judgment in mixing and applying colors can be
acquired only by practice. When a combination tint, such
as bro\\rn, is required, the draftsman must estimate how
much coloring is required and provide accordingly. He is
liable to use too much color producing a heavy tint, which
is almost certain to become streaked when applied. A
separate brush should be used to take up each color, the



808 MAPPING.

brush being moistened and rubbed on the cake. A tinting
dish of either glass or porcelain contains the water. The
brushes carrying the colors are dipped into the water, each
giving off its proportion of color. The water is then stirred
until every particle of color is dissolved. If the tint is too
light, add more color; if too heavy a common fault add
more water until the proper shade is obtained. Any tint is
deepened by repeating the application of it. When a tint is
to be shaded from light to dark, give the entire surface one
coat, which will give the lightest shade. Decide how many
coats are to be applied to produce "the deepest tint and
divide the length of the surface into the same number of
equal spaces. Beginning at the top of the surface to be
shaded, apply a second coat, stopping one space from the
bottom. Then take a clean brush and dip it into clear
water and wash the edge of the second coat at its finishing
line, brushing downwards, taking up in the brush all excess
of coloring matter. Another coat is then applied, com-
mencing again at the top and stopping two spaces from the
bottom, washing down the edge with clear water. The
paper must not be allowed to dry between the successive
applications of the tint. If from any cause it should be-
come dry, the entire surface must be moistened with clear
water before another application of the tint. Careful prac-
tice will enable the student to produce a smooth tint.
When a marbled effect is desired, first cover the entire sur-
face with one tint and then apply the other in shorter or
longer strokes of the brush, according to the effect which it
is desired to produce.

In tinting shore lines, first trace the outline of the shore
with a brush moistened with clear water, extending the wash
as far as the tint is to be used. Prepare, a color dark blue in
shade. Next dip a fine brush in the color and trace the out -
line of the shore. The adjoining paper being moist will cause
the color to run. Then moisten a brush in clear water and
wash the shore line, the strokes of the brush being drawn
from the shore. The effect will be a dark blue shore line
shaded to light blue. The dark brown color for roads is



MAPPING. 809

produced by adding India ink to the brown representing
grass land.

1387. Scales. The scale of a topographical map
should depend upon the character of the work involved, but
should always be large enough to clearly admit all necessary
details without making the map unwieldy. The work should
be so well done that dimensions may be accurately scaled
from the map without any calculation. For small plats,
such as public squares and small parks, 50 feet to the inch
would be a suitable scale, admitting the smallest detail.
For larger areas, such as town sites, extensive parks, sub-
urban resorts, etc., a scale of 200 feet to the inch is com-
monly used. The scale must be reduced in proportion as
the area is increased. Published topographical maps are
usually made to a scale of one inch to the mile, admitting
of the representation of all towns, villages, farms, woods,
isolated buildings, and every stream of 600 feet in length,
and every hill of 100 feet in height and 500 or 600 feet in
horizontal extent.

On a scale of two inches to the mile, the various features
of the ground can be clearly and accurately represented.
All streams of 300 feet in length, every pond not less than
50 feet broad, and all towns, villages, roads, foot-paths,



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