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farms, and isolated buildings.

A scale of six inches to the mile is best for military pur-
poses, admitting of a complete delineation of a country. In
all cases the character of the surface and the purpose of the
map should determine the scale.

1388. Size of Maps. Maps for use in the field may
vary in size from 18 by 24 inches to 24 by 30 inches. Both
sizes are suitable for railroad work. The lines should be so
arranged on the different sheets that they may be fitted
together, making a continuous map of the line of survey.
The sheets should be numbered in regular rotation, and
when pinned together they will appear as shown in Fig.

Where possible, arrange the sheets so that each curve



with its center and limiting radii may come on the same
sheet. Sometimes this can not be done. The points where
the different sheets join on to each other should be fixed by
a line drawn at right angles to the center line or radial line

FIG. 354.

at the point of junction, as at A or B. This simplifies the
work of fitting the sheets, and greatly promotes accuracy.

1389. Lettering. Legibility and uniformity are the
requisites for good lettering. Ornamental letters, ex-
cepting for titles, are entirely out of place, and they are
only admissible for titles of very elaborate maps. All let-
tering in the body of the map or details should be in
italics. Small letters should be two-thirds the height of
capitals, ordinary capitals of an inch in height, and small
letters f of or T ^ inch in height. Uniformity in spacing
letters is as important as uniformity in size. There is no
work where practice is more essential, if skill is to be ac-
quired, and nothing adds more to the finish of a drawing
than good lettering, while poor and slovenly lettering will
rob of all merit an otherwise perfect drawing.

1390. General Instructions. If the entire map is
to be contained on a single sheet, judgment is required in
fixing the direction of the first course so as to attain that
result. The points of the compass must also be in their


natural order, viz., North at the top of the map and South
at the bottom.

The outline of the map will determine the position of the
title. Veryyfr/r lines are a blemish rather than a merit, and
heavy lines are likewise to be avoided except when used for
shading or boundaries. Boundaries of private property are
represented by bold, full lines, and those of state, county,
or municipality by heavy broken and dotted lines. All
dimensions should be expressed in figures, and all impor-
tant lines and objects briefly but accurately described.


1391. Need of a Railroad. This subject presup-
poses that there is, beyond a doubt, need, both present and
Prospective, for the railroad whose location is to be decided

1392. Available Capital. The first duty of the
Chief Engineer is to know Jiow much money those having the
direction of the enterprise, commonly known as the company,
have or can command, as all subsequent operations will be
governed by that fact alone. Having obtained that infor-
mation, he collects all available maps of the country to be
operated in, and from them derives a general knowledge of
the mountain ranges, valleys, rivers, together with their
tributaries, and the location of all towns and villages lying
within that territory, their relative size and importance.

1393. Terminals. The terminals or extremities of
the proposed railroad are known, and the first problem be-
fore the engineer is to determine the general route which
the line connecting them should take. A careful study of
the maps in hand will indicate to him the different possible
routes whose comparative merits he can know only by care-
ful investigation. The number of these possible routes will
probably be further reduced by the location of certain towns
which must be reached for traffic considerations. These
towns will divide up the line into two or more sections, each
offering considerable range in choice of location, which in-
dicate to the engineer the scope of the country to be covered
by the reconnaissance.

1394. Important Considerations. The engineer
should preserve an optimistic habit of mind, believing noth-
ing to be too difficult to be overcome, and fully expecting


to find a line in every way superior to that which had been
regarded as possible. It is of the highest importance that
he should regard the proposed line from a business point of
view, and be able to distinguish between what is commer-
cially important and physically important. He should keep
constantly in mind this vital fact, viz., that a line of rail-
road is built for the purpose of making money for its project-
ors; that any expenditure which will add proportionately to
the earning power of the road is wise, and that any which
will not is criminal waste.

1395. Relative Economy. The engineer must,
however, be able to distinguish between wise and unwise
economy. Because a line is brought to sub-grade cheaply, it
is not necessarily economical grading. It requires an average
continuous cut and fill of 7 feet, with the usual proportion
of masonry, to equal the cost of the superstructure, i. e.,
ties, rails, fastenings, and ballast, while the cost of rolling
stock, machinery, buildings, etc., of an active road, cost
nearly as much as roadbed and track complete.

1396. Towns and Terminals. Towns, which are
always the main sources of traffic, and terminals, which,
besides being sources of traffic, are the main points of
traffic exchange, are considerations of vital importance to
the road. No expense within the possible reach of the com-
pany should be spared in reaching the heart of towns and in
providing the best traffic facilities. A small saving in time
and a small increase in comfort will, other things being
equal, secure the traffic. Where the new line comes into
competition with old and favored lines, no pains which tact
or ingenuity can devise should be spared to induce favor and
patronage. It is at such a juncture that tact and enterprise
count. No source of business, however insignificant, should
be overlooked, and every point gained should be held at any
reasonable cost. Provide ample terminal grounds at any
possible cost; with them a new road will have a hard fight,
while the lack of them places the road at a great disadvan-
tage from the first, and may cause its ruin.


1397. Comparative Cost of Different Lines.

In order that the engineer may correctly estimate the com-
parative cost of different lines, he must know the actual
cost of work of various kinds, and be able, from his exami-
nations of the country, to properly classify it. Experience
in the location and construction of other lines will alone
enable him to decide between the comparative merits of the
different routes.

The almost universal fault of engineers is to underesti-
mate cost, a fault common to all persons who are about to
undertake construction of any kind. Experienced engineers
make it a rule to add 10 per cent, to the estimate which is
intended to cover all possible cost.

1398. Considerations Which Determine the
Route. Traffic and engineering considerations will usually
reduce the possible routes to tivo if not to one, thus narrow-
ing the field of operations. The work of reducing the traffic
and engineering possibilities of a section of country to their
lowest terms is emphatically the work of the chief engineer,
and is embraced in that most important, though much mis-
understood, term, viz., the reconnaissance. Let the young
engineer keep prominently before his mind that the largest
half of a railroad survey is the reconnaissance. Let him
ponder well the varied interests and problems which con-
front him, and let him know his country before he drives a
stake. This knowledge can be had only by hard work and
a good deal of it.


1 399. General Directions. Having provided him-
self with the best available map of the section immediately
in hand, an aneroid barometer, and a guide who is familiar
with the section, the engineer is ready for a start. He
should avoid highways if he is to acquire the knowledge he
is seeking, as they give the traveler an erroneous impres-
sion of the character of the surrounding country. He un-
consciously believes because the " walking is good " that the


surrounding country is smooth and tractable, and obstacles
to railroad building few and insignificant. On the other
hand, by taking a cross-country route, he will be likely to
exaggerate those obstacles, simply because they have im-
peded his travel. All experience goes to prove that in
America, at least, the railways avoid the highways; not
through the intent of the engineer, but, as it were, in silent
condemnation of the incapacity of those who directed their
building. The engineer should keep constantly in mind
that his examinations are not to be confined to the strip of
country within his immediate vision, but are to cover a
range of several miles on either side of his line of march.
Much information he can obtain from his guide; more he
must find out for himself taking nothing for granted where
a doubt is raised. Very often an apparent obstruction
which, did it really exist, would effectually bar the way,
will disappear upon a careful inspection of the country, or
at the worst prove an insignificant obstacle compared to
those already passed. Obstacles to travel are not neces-
sarily obstacles to railway building. Narrow defiles, ob-
structed by boulders, underbrush, and timber will, when
cleared, appear comparatively smooth.

1400. Use of the Hand Level. The hand-level is
of the greatest value, and should be in constant use. The
unaided eye is of little use in estimating comparative
elevations. The hand level determines relative heights,
constantly affording needed information and saving much
time, which, without it, would be spent in useless tramping.

1401. Keeping Notes. A careful record should be
kept of all streams encountered; their direction, and of
what larger streams they are tributaries.

The sizes of different streams in the same section, to a
certain degree, determines their relative elevations. The
larger the stream the lower its elevation. The velocity of
its current, in a measure, indicates the grade of a stream,
though a fall which would make a torrent of a river would
give but a feeble current to a shallow stream. The recon-



naissance should cover a complete section of the proposed
line before the work of actual survey is commenced, though
it is not to be considered as complete until the final location
is fixed.

14O2. Deceptive Appearances of Country. The

natural eyesight is easily deceived, and rarely gives to
objects their true relative proportions. Two reasons for
this deception are the following:

First, the eye foreshortens the distance in an air line, and
exaggerates a lateral offset. This fact is illustrated by
Fig. 355, in which let the points A and B, which are 10,000

^>v^,^^ 10000

FIG. 355.

ft. apart, be in an air line between two towns, and suppose
this line to cross a ridge, the highest point of which is at C,
and that the ridge flattens out at D, 2,000 feet from C, the
middle point of A B. To the inexperienced, the offset C D,
as seen on the ground, will be greatly exaggerated, appear-
ing to be fully one-half the straight line A B, and the con-
viction will follow that in passing from A to B by way of C,
not only will a great deal of curvature be introduced, but
the length of the line will be so greatly increased over that
of A B as to make a careful consideration of the route out
of the question ; even though the line A B should require
steep grades and a heavy cut at C. This exaggeration is
apparent when we find by calculation that the distance from
A to B by way of D is only 770.33 ft. greater than the
direct line between A and B. This illusion of the eye ex-
plains the aversion to swinging the line, too common among
engineers, and the undue importance attached to good
alincinent. The chances are four to one that the line
A D B is immensely superior to the line A B, both in cost


and grades, while the increase in distance of the line A D B
over the line A B is less than 8 per cent.

Frequently a deflection, which will not, in reality, add
more than 15 per cent, to the length of a line, will appear
to double it, and the deplorable mistake is often made of
adopting the air line, even though it cost 25 per cent, in
excess of what the deflected line would cost.

Second, the eye exaggerates the sharpness of projecting
points and spurs and the degree of curvature necessary to
pass around them. All slopes when looked at from in front,
are exaggerated by the eye. Few mountains have slopes
exceeding 1 to 1 or 33, yet the eye will estimate such a
slope at from 45 to 50.

In running the line A B C D, Fig. 356, the engineer, if he
were to accept his natural estimate of the angles at B and C,

would make the angle at C about twice as large as the angle
at B, even though he had walked over the line. The reason
for this is that while standing at any point on the line B C,
his view of the line C D is cut off by the profile E C of the
hill in front, and, in spite of himself, the unseen will be
distorted and invariably magnified.

Nowhere is the proverb, "appearances are deceiving,"
so true as in an apparently smooth or gently rolling country.
The undulations are so gradual that their aggregate is rarely
suspected. Abundant experience goes to prove that an air
line in such a country is only possible at the cost of heavy
grades and long and heavy cuts and fills. To avoid them,
frequent deflections must be made, introducing curvature
in proportion, though the increase in length of line is in no



degree proportional to the saving in cost of construction and

1403. Discredit All Unfavorable Reports. An

unfavorable report of a locality, more than any other, should
challenge a careful examination. The inexperienced are
easily daunted by obstacles which are really insignificant.
A section heavily timbered and covered with boulders, and
appearing to them as forbidding in the extreme, would likely
show an alinement and grades incomparably better than the
line of their choice. In reconnaissance it is the unexpected
which happens, and the line which appears least promising
will often prove, by far, the best.

1404. Choice of Lines. Never believe that only one
line is possible. There are always two, and generally sev-

FIG. 357.

eral. The important question is, which line is the best, and


that is the one to settle upon. The following instance well
illustrates this point. The facts in the case are shown in
Fig. 357. The line had followed the river A B for several
miles, keeping a uniform grade of about 30 feet per mile. It
became necessary to leave the river valley and climb a ridge
in order to reach a town lying in another valley. The entire
country was thickly covered with timber and undergrowth,
and consisted of abrupt, irregular hills, called hog-backs.
The brook C was known to the engineer, who endeavored to
trace it to its junction with the river, but the brook lost it-
self in a cedar swamp at Z>, and it was impossible to find the
outlet. After repeated effort to find the outlet and encoun-
tering each time the ridge E which lay between the river and
the valley D C, he continued the line up the river, crossing
it at B, where a precipitous ledge prevented further progress
along the river, and crossing the neck of land F, and the
river at G, commenced to climb the ridge doubling about
the sharp headland at //, and then swinging backwards,
making the line K L with a heavy fill at M. This seemed
the only possible line, but it was so rough and crooked that
the engineer determined to make another trial. He spent
two days in hard tramping during a continual downpour of
rain, discovering the narrow opening at N through which
the brook found its way. He also found the brooks P and Q,
and blazed a line through from E to K. A line was then
run, following this course with the most satisfactory results,
saving two river bridges and three miles in distance, though
getting through the ridge at E entailed a heavy cut. The
railroad company was opposed to any further investigation
after the completion of the first line, as a month of hard
work had been expended upon it. Yet the saving in first
cost accomplished by the adoption of the second line over
the first would have paid the engineering expenses of the
entire line of 100 miles. In general, a better line than the
one already in hand can be found by looking for it.

14O5. Advantages of Valley Lines. Wherever
possible, stick to the valleys. Bottom lands, though low*


lying, are generally above flood line, or, if below it, are only
covered by back-water, else they would have been long since
washed away. Though a crooked channel may necessitate
frequent and sharp curves, yet they are more than compen-
sated for by the low grades fixed by that channel. As fre-
quently happens, the bends in the channel are caused by
projecting heads of hills. These sharp and often rocky
points usually require but short cuts, and furnish the best
of material for the adjacent embankments.

Notes should be kept of all important information gained.
Points where two promising lines diverge should be so
marked as to be readily recognized.

The reconnaissance being completed and all economical
and topographical questions settled, the next duty of the
engineer is the preliminary survey. The party should be
organized and all ready for service the moment the recon-
naissance and general route is decided upon.

14O6. Organization of Party. The size of the
party will depend upon the character of the country in which
the work is to be done. If thickly settled, smaller; if thinly
settled, larger.

A well-equipped party in ordinary country should number
sixteen men, as follows: The transit party, comprising
chief of party, transitman, two chainmen, three axmen,
one stakeman, and one back flagman; the level party, com-
prising the leveler, rodman, and one axman, and the topo-
graphical party, comprising the topographer and two assist-
ants. The last to be named, though not the last in point
of importance, is the teamster, who should be provided with
a strong, active team, and spring wagon that will not break
down. It is a most wasteful economy to require a party tp
walk from two to five miles before commencing work, and
then to quit work in time to make another long tramp be-
fore reaching shelter. A chief of party who does not know
the necessity for a team and insist upon having it, is not fit
for the work in hand. No company will refuse to provide
it, if the matter be properly presented, yet many parties are


deprived of this important part of the outfit. If the party
are living in camp, a team is an absolute necessity for
moving the camp, which will be done at least once a week,
and usually once in three or four days.

1407. Camp Outfit. For camp work the following
outfit will be necessary:

Two wall tents with flies, or extra roofs, for the accom-
modation of the men, and, if the work is to be carried on
during the winter season, a tent must be provided for the
team ; a sheet-iron stove and provision chest for the com-
missary ; a cook who can prepare wholesome food and plenty
of it, and keep himself and belongings clean and orderly; a
drafting table, which is nothing more than a large draw-
ing board, a straight-edge and triangles, an ordinary pocket
case of drafting instruments, together with a beam com-
pass, will answer for all preliminary drafting. Drawing
and profile paper, note books, etc., are carried in a camp
chest. Each man provides his own bedding, which consists
of blankets alone.

The field instruments will comprise the following, viz. :
A surveyor's compass, plain transit, and transit poles, Y level
and Philadelphia leveling rod, aneroid barometer, clinom-
eter, slope rod, chain, axes, marking crayons, tacks, and
stake straps about the width and length of ordinary trunk
straps. A supply of stakes should be kept constantly on
hand. If possible, have these of light, well-seasoned wood
(pine is best) and of the following dimensions: Length
2 ft. G in., width 2 in., thickness % in., and planed on one
side so as to admit of easy and plain numbering. Special
conditions may require additional equipment, but the above
outfit will meet all ordinary requirements.

1408. The Compass for Preliminary Work. If

the section be comparatively free from iron deposits, the
preliminary line should be run with the compass, for in spite
of small inaccuracies in alinement due to errors in reading
the needle, the average accuracy of a number of readings
will closely approximate to those read with the transit


vernier. The comparative advantages of compass and tran-
sit for preliminary railroad surveys was discussed in Art.
1217. vSuffice to say, that where the conditions warrant
it, the compass is always the more economical and expedi-
tious instrument. If, however, iron exists in quantities
sufficient to hinder the perfect freedom of the magnetic
needle, the compass must be discarded for the transit, with
the injunction to never record an angle without first check-
ing it ; and after recording, read the angle a second time.
The assurance of accuracy is worth many times the labor
and care of checking work.


14O9. The Starting Point. In general, the start-
ing point of the survey will be at an extremity of one of the
sections into which the proposed line is divided. If it is to
connect with some already existing line, a point on that line
is taken; if not, a street line or some other fixed boundary
is chosen and the line tied into it. The chief of party ac-
companied by a flagman, goes ahead and fixes the points
where the angles are to be taken. The flagman carries, be-
sides the transit pole, an ax for making plugs, one of
which he drives flush with the ground at every transit
point. A galvanized tack, or, better still, a small galvan-
ized nail, is driven in the center of the plug and the transit
pole (flag) held on the point while the transitman reads the
angle. A point having been fixed, and the flag set up, the
transitman measures the angle between the boundary at
Station and the first course. The angle and bearing of the
line being recorded, the transitman walks rapidly to the
point where the flag is standing and sets up the instrument
at that point. The head flagman should carry about a dozen
pieces of red flannel to be used as targets. As soon as' a
transit point is set and the transitman has signaled that the
angle is read, the flagman should tie a piece of target flan-
nel to a light stake of about the same length as the transit
pole, and plant the pole firmly in line directly behind the


plug or transit point. This affords the chainman a good
target for lining in, and allows the flagman to join the chief
of party who has gone ahead to select another transit point.
The transit being set up, a backsight is taken to a flag held
at the starting point (Station 0). The bearing is then
checked and the angle turned to the next point ahead. The
chainmen having come up with the transit, they report the
number of the station of the transit point to the transitman,
who records it in the transit book. He then directs the
chainman on the next course, reads the forward angle and
records it together with the bearing of that course, and then
moves up to the next transit point.

1410. The Level Party. The level party follows
the transit party as closely as possible. The levels of the
proposed line and the line with which it is to connect should
be referred to the same datum plane, so as to secure a con-
tinuous profile; especially if the levels of the established
line are referred to the sea level. If such a base is not
practicable, an elevation for the starting point must be as-
sumed, but of such a height as will bring all elevations of
the proposed line above the assumed datum plane.

In case the country is wooded, with the added hindrance
of thick underbrush, the transit party will of necessity move
slowly, and the level party will consequently have much

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