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span, are sometimes estimated at a fixed price per 1,000 feet
for lumber, and a fixed price per Ib. for iron, but generally
a special estimate is made for each bridge. The cost of
bridges increases rapidly as the span increases. In metal
bridges the cost will increase about as the square of the



span, i. e., if one bridge has twice as great a span as another,
the first will cost the square of 2 or 4 times as much as the

1444. Quantities. The material to be handled in
grading the roadbed is generally estimated by level cuttings,
which process assumes that the cross-section surfaces are

level, and the areas are calculated from the center cuts and
fills. Let Fig. 377 represent the actual cross-section at a
given station, and Fig. 378 the cross-section based upon the
center cut. The area of the section A B C D in Fig. 377,
calculated from the actual cross-sections, is 160.78 sq. ft.
The area of the section A' B' C D\ in Fig. 378, calculated

Cut 6.4 ft.

^J5.4- 1 15.4'^ -

Cut 6.4ft

Cut 6.4 ft.

9- 1 &

FIG. 378.


from a level section, with the same center cut, viz., 6.4 feet,
is 156.16 sq. ft., giving a discrepancy of 4.62 sq. ft. ; that is,
the area of the section, calculated by level cuttings, is 4.62
sq. ft. less than the area calculated from the ^actual' cross-
sections. This deficiency is about 3 per cent., but where
the slope is very steep, the difference increases rapidly. As
the invariable custom is to add 10 per cent, to the estimated






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cost, such addition will fully cover any deficiency resulting
from table calculations. Where time is not an object, it is
good practice to take the slopes with a clinometer and plat
them on cross-section paper. The estimate thus obtained
will be a close approximation to the actual quantities
handled in the work of construction. For work in the
Northern and Middle States the following rates of slope are
standard: For embankments, H horizontal to 1 vertical;
for earth cuts, 1 horizontal to 1 vertical, and for rock cuts,
horizontal to 1 vertical. In Western and Southern States
it is the usual custom to give to cuts the same slope as to
embankments, viz., 1 horizontal to 1 vertical.

1445. Trautwine's Engineers' Pocket Book con-
tains complete tables of level cuttings for standard widths
of roadway, both single and double track. The slopes are
given for earthwork, both excavation and embankment.
The quantities are calculated for sections 100 feet apart. If
the sections are taken oftener than each 100 feet, the quan-
tities will be proportionally less. The table of Level Cut-
tings shows the arrangement for single-track excavation,
roadway 18 feet wide, slopes 1 horizontal to 1 vertical.

The use of this table is explained as follows: Suppose the
center cut at Station 10 is 1.5 ft. and the center cut at
Station 11 is 3.0 ft. The sum of these two center cuts,
1.5 + 3.0 = 4.5 ft. The mean or average center cut at

4 5
these stations is, therefore, - 1 = 2. 25 ft. As the nearest


tenth is always used, we will call the average cut between
Stations 10 and 11, 2.2 ft.

Referring to the table, we find in the column headed
depth of cut infect, the figure 2, and on the same horizontal
line, under the column headed .2, we find 164.0, which is
the number of cubic yards of material to be excavated
between Stations 10 and 11.

The quantities are given for center cutsfrom.l foot to 60
feet. For cuts greater than 60 feet, the quantities are
calculated for only even feet.



1446. Sections. The line is divided into lengths of
one mile each, called sections, which are numbered in regu-
lar order, the first mile of the line

being section 1, the second mile section
2, and so on. At the division points,
i. e., where one section ends and another
begins, posts are set up with boards at-
tached, facing in both directions, with
the number of the section towards which
they face written in large figures. See
Fig. 379.

The section boards enable one to
readily locate any particular part of the

1447. Right of Way. Before
construction can be commenced, the
right of way must be secured, a matter
always attended by more or less difficulty.
The standard width of right of way is

100 feet, though, in some cases, but 4 rods or 66 feet is
adopted, with additional widths wherever needed.

Where the local needs for the road are great, and the
enterprise popular, much right of way is often donated, a
nominal sum, usually one dollar, being paid as considera-
tion. The ordinary mode of securing right of way is by
direct purchase. The company employs an agent specially
fitted for his business, who makes the most advantageous
bargains possible with the different owners. When there is
failure to agree on price, a common alternative is to leave
the question to three arbitrators, each of the parties to the
transaction choosing one and agreeing together upon the
third. The arbitrators unite upon a valuation which the
contracting parties have agreed to accept. Occasionally, an
owner, taking advantage of the situation, attempts extor-
tion, in which case the only recourse is to the law of emi-
nent domain. Articles of condemnation are taken out and
appraisers appointed by the court, who fix the amount of


compensation. The process is always attended by expense,
delay, and vexation, and should only be a last resort.

1448. Right of Way Maps. A careful survey is
made of each separate piece of property bought for right
ot way or station grounds, and stone corners established for
future reference. These surveys should be platted in a
"right of way" book in the same order in which they occur
on the line, and a copy of the contract for and description
of the property written on the same page or that adjoining
the plat. The plat should specify content, boundaries,
corners, and any information which may be of future use.
A copy of the contract and a tracing of the plat is delivered
to the person or persons from whom the property is bought.

1449. Specifications. Specifications describe the
manner in which the work of construction is to be con-
ducted and the materials to be used in structures.

Specifications are of two kinds; viz., general, those de-
scribing the different general classes of work, and special,
those referring to a particular structure or other work
requiring special plans or processes. In this work only
general specifications will be given.

A., B., & C. R. R.


1. Clearing. The surface is to be cleared the full
width of right of way and such additional width as the
engineer in charge shall direct, of all trees, bushes, and
other perishable matter.

2. Grubbing. In cuttings, and in embankments where
the fill is two feet and less, all trees and stumps between the
slope stakes must be grubbed out; where the fill is more
than two feet, all trees and stumps must be cut down even
with the surface of the ground. No payment will be made
for grubbing.


3. Grading. Under this head will be included all ex-
cavations and embankments required for the formation of
the roadbed, side tracks, and station grounds; the founda-
tion pits for bridges, culverts, and cattle-guards; the cutting
of ditches and drains contiguous to the roadbed; all excava-
tions and embankments in constructing farm and highway
crossings, and in the changing of channels for streams.

4. Borrow Pits. The embankment shall be con-
structed from material borrowed from the right of way.
No embankment shall be constructed from material de-
posited by casting without special permission of the engineer
in charge. If borrow pits are required outside the right of
way, they shall be procured by the railroad company.

5. Provision for Settling. Cuts and ditches shall be
measured in excavation; all other work shall be measured
and paid for in embankment. The embankments shall be
made from 5 to 10 per cent, higher than the established
grades. This additional percentage is an allowance for
shrinkage, and shall be fixed by the resident engineer. No
allowance for such shrinkage shall be made in the estimate.

6. Single-Track Work. In single-track work the
roadway shall be eighteen feet in width at sub-grade in cuts,
and fourteen feet in width on embankments. The side
slopes of earth cuts shall be one horizontal to one vertical,
and of rock cuts one-quarter horizontal to one vertical, un-
less otherwise specified by the engineer in charge. The side
slopes for embankments shall be one and one-half horizontal
to one vertical. A berme six feet in width shall be left
between the slope stakes and the edge of the borrow pits.

7. Double-Track Work. In double-track work the*
roadway shall be twenty-eight feet in width at sub-grade in
cuts, and twenty-four feet in width on embankments. Side
slopes of earth cuts shall be one horizontal to one vertical;
of rock cuts, one-quarter horizontal to one vertical, unless
otherwise specified by the engineer in charge. The side
slopes for embankments shall be one and one-half horizontal


to one vertical. A berme six feet in width shall be left
between the slope stakes and the edge of the borrow pit.

8. Borrow Pits. A space three feet in width shall be
left between the borrow pits and the right-of-way lines.
The slopes of borrow pits shall not be steeper than one and
one-half horizontal to one vertical, and shall generally be of
such depth as will secure proper drainage.

9. Ditches. All excavations shall be finished with side
ditches of such dimensions as the engineer shall direct, and
to prevent the washing of slopes, ditches shall be cut on the
up-hill side, such ditches to be not less than four feet from
the top of the slope.

10. Excavation. The classification for all excavated
material will be as follows:

Earth will include clay, sand, gravel, loam, decomposed
rock, and slate, and all other matters of an earthy kind, how-
ever hard, stiff, or compact, and all boulders containing less
than three cubic feet each.

Loose rock will include all stone and detached rock
found in separate masses, containing not less than three
cubic feet nor more than one cubic yard; also, all slate,
coal, or other rock, soft or loose enough to be removed with-
out blasting, although blasting may be resorted to; also,
stratified limestone in layers eight inches thick and under,
separated by strata of clay.

Solid rock will include all rock in masses of more than
one cubic yard which can not be removed without blasting.

11. Foundation excavation above the general water
level at the time shall be excavated by the contractor and
paid for at his grading prices. The residue of foundation
work will be executed by the contractor, and paid for by
the company at actual cost, with ten per cent, added for
contractor's supervision, use of tools, etc. The price per
yard bid for masonry will include centerings, scaffoldings,
and all other expenses connected with the work, excepting
the foundation work above specified.


12. Tunnel Excavation. The price for tunnel ex-
cavation will include all excavation between the portals of
the tunnel proper, and within the area of the cross-section,
as determined by the engineer, and it will include also all
temporary supports, scaffolding, etc. The area of the cross-
section for tunnel excavation will be measured six inches
outside the wall and arch, and all excavation outside of this
cross-section will not be paid for unless in the opinion of the
engineer such irregularities could not be prevented by the
exercise of proper care and judgment in excavating, and
paid for at such prices as the engineer shall determine.

13. Masonry. Masonry shall be built according to
plans furnished by the engineer, and estimated and paid for
by the cubic yard. Masonry in which mortar is required shall
be kept well wet while being laid, and every stone shall be
clean and thoroughly wet when laid. Arches shall be built
on substantial centers extending the entire length of the
arch, and the mode of construction, as well as the plan, shall
be approved by the engineer. Centers shall not be removed
or loosened without the direction of the engineer. The
price per yard shall in all cases include the furnishing of
centers, scaffolding, and all other cost and expense incidental
to the completion of the work. All joints of face walls of
masonry laid in mortar shall be suitably pointed, and the
work finished to the satisfaction of the engineer.

Tunnel Masonry. The masonry for tunnels and all
bridge piers and abutments shall be of Rock Face Range
Work. All of the arch stones shall be well and smoothly
cut on the beds, ends, and face, and shall be laid so that
their beds shall be at right angles to the tangent of the
curve. The beds of each stone shall have full and solid
bearings, and the joints shall be close and straight.

Walls and arches shall belaid in regular courses of uniform
thickness. No course shall be less than four inches in thick-
ness. The faces shall be Rock Face with edges pitched to
straight and true lines.

The vacancies behind tunnel walls and above tunnel arches


shall be filled with concrete or dry packing, at the discre-
tion of the engineer. All packing must be well rammed in
place as the work progresses.

First-Class Masonry. In all first-class masonry the
stones of each course shall be gauged to the same thickness,
and after each course is laid and grouted or filled with mor-
tar, the tops of the stones shall be dressed so as to bring the
top of the course to a common level.

Stretchers shall be not less than three feet in length, with
bed not less than sixteen inches. Headers shall be not less
than eighteen inches in width, nor less than three times
the thickness of the course in length. Stretchers and
headers should be in the proportions of 3 to 1. All face
stones shall be dressed full to the square for their entire
length and width, and shall be so cut and laid as to have
a full bearing for their entire bed. All joints shall be
close and straight, and be so broken as to make a perfect

Backing shall be of good-sized and well-shaped stones and
so dressed that each stone shall lie firmly on its bed. The
backing shall be laid with reference to each succeeding
course, affording good header bearers and so bonding the
whole into one solid mass. All stones shall be laid in mor-
tar, and if the engineer shall so direct, the vertical joints
shall remain open until the course is finished. All unfilled
parts of the wall shall be filled with mortar or grout. The
tops of the walls shall be coped with large broad stones, not
less than three feet in length, the same to be well-dressed
on the top and ends, and all face joints pointed with good

Culvert Masonry. Arched and box culverts shall be
built of good-sized and well-shaped stones, and laid dry
unless otherwise directed by the engineer in charge. Stones
shall be straightened on faces and ends with fair proportion
of headers, and laid with joints broken so as to form a com-
pact and substantial body. Covering stones shall be of such
length and thickness as the engineer in charge shall direct.


The top courses of wing waits shall be of wide stones with
good joints, so as to form a good and smooth coping.

14. Pavement. Between the side walls and at the
ends of culverts and bridges where required, paving will be
laid of good smooth stones set on edge and well fitted, so as
to make a close, smooth surface. Paving shall be of such
thickness as the engineer shall direct, and it shall be secured
at ends and sides by curb stones not less than two feet in
depth. To prevent undermining, broken stone shall be
deposited outside the curbing. Paving will be paid for by
the cubic yard.

15. Mortar and grout shall be made of clean sharp
sand and fresh slacked lime, in the proportions of one part of
lime to two of sand. Mortar shall be thoroughly mixed
and allowed to stand until all particles of lime are thoroughly
slacked. Hydraulic cement to be substituted for lime at
the discretion of the engineer, the difference in actual cost
to be refunded to the contractor. The proportion of the
ingredients of mortar and grout may be varied at the dis-
cretion of the engineer.

16. Protection. When required by the engineer, em-
bankments will be protected by cribbing built of round logs
and rilled with stone, or riprap laid with beds at right angles
to the slope of embankment, affording a close and generally
smooth surface. Contractors shall hold themselves in readi-
ness to perform such work with promptness and dispatch.
Cribbing will be paid for by the lineal foot, and riprap by
the cubic yard both to be measured in place.

17. Piling. Piles shall be of white or burr oak, long
leaf pine, or other suitable timber, sound and without loose
or rotten knots. They shall measure not less than seven
inches in thickness at the small end, and average not less
than eleven in thickness. The bark must be removed before

18. Driving. Piles must be driven at the places staked
out for them by the engineer in charge, and they must be


driven, if the engineer so desires, to such a depth that a
hammer weighing 2,000 pounds, falling upon the pile from
a height of twenty feet, will not sink the pile more than one

19. Timber. All timber shall be of sound, straight-
grained white or long leafed southern pine or other suitable
timber, free from rotten knots or shakes, and with no sap
extending more than two inches from any edge.

20. Framing. The framing shall be done in the most
workmanlike manner and in accordance with plans furnished
by the engineer.

21. Inspection. The kind and quantity of all material
in the work shall be subject to the approval of the engineer
in charge. Timber shall be estimated in place and paid for
by the thousand feet, board measure. All iron used in
structures will be paid for by the pound.

22. Monthly Estimates. During the progress of the
work, on or about the first of every month a monthly esti-
mate shall be made of the kind, quality, amount, and value
of work done during the preceding month, eighty-five per
cent, of which value will be paid to the' contractor on or
about the fifteenth of said month, and when the work is
completed and accepted there shall be a final estimate made
by the engineer of the quantity, character, and value of the
entire work, according to the terms of the contract, and the
balance, after deducting the several monthly payments, and
upon the contractor giving release to the company from all
claims or demands whatsoever, will be paid in full.

23. The contractor shall render an account monthly,
through the proper superintending engineer, of any extra
work which he may have been authorized to do ; and to pre-
vent disputes hereafter, it is hereby understood that no bills
for extra work will be allowed unless authorized and ordered
in ivriting by the engineer in charge, and the bill for said
extra work presented at the end of the month in which the
work was done, and approved by said engineer.


24. During the progress of the work and until it shall
be completed and accepted by the company, it shall be the
duty of the contractor, a his own expense, to sufficiently
guard and protect the same by barriers, fences, or otherwise,
so as to prevent travelers or other persons from sustaining
injury to themselves or property by falling into any excava-
tion or running over any dangerous fill or embankment, or
over or against stumps, timber, or any material, or in any
other way whatsoever; and in blasting stone, the contractor
shall use the utmost precaution and care to avoid injuring
persons or property, and the contractor shall save and keep
the company free and harmless from the payment of any
damage for injury to persons or property arising from any
malfeasance or negligence of the contractor or of any of his
sub-contractors, agents, or servants.

25. The contractor shall not let or transfer his contract
or any part of it, or withdraw his personal attention there-
from, without the consent of the engineer.

26. The contractor shall put on and maintain night
forces at such points and to such extent as the engineer shall

27. In all disputes the decision of the engineer shall be

28. By engineer is meant the chief engineer.

1 45O. Advertising for "Work. A classified estimate
is made of the amount of work in each section, and the road
is advertised for contract. These advertisements name a
date for the opening of bids. Contractors are provided with
a printed copy of the general specifications and of the esti-
mated quantities in each section, and are allowed to take
such notes as they may require from the map and profile.
In walking over the line they can readily locate any par-
ticular section from the section boards.

1451. Reservations. The company should invari-
ably reserve the right to reject any or all bids, in order that


they may shut out irresponsible men or prevent a combina-
tion of contractors from charging exorbitant prices for

1452. Bond. Contractors should be required to fur-
nish a bond signed by two responsible parties to insure the
proper fulfilment of their contract. This bond is usually
to the amount of ten per cent, of the estimated cost of the
work undertaken. The contract specifies the date on or
before which the contractor shall complete the work, and
often specifies a forfeit to be imposed in case of any default
on the part of the contractor to fulfil the conditions of his


1453. The Engineer Corps. The engineer corps in
charge of construction differs in organization from that in
charge of location. In general, when construction is .com-
menced, it is prosecuted with vigor throughout the entire
line, and, as the work requires constant inspection, the
force of engineers is considerably augmented.

1454. Subdivisions of the Line. The entire line
is divided into sections of about 30 miles each, called divi-
sions, each division being placed in charge of a division
engineer. The divisions are further divided into lengths
of about 10 miles each, called residencies. Each residency
is placed in charge of a resident engineer.

1455. The Division Engineer, His Authority
and Duties. The division engineer has general charge of
an entire division and is directly accountable to the chief
engineer, from whom he receives general orders relating
to the work of his division. He should go over his entire
division twice each week, giving particular directions to the
resident engineers for the conduct of the work and main-
taining a general supervision of the whole. His office
should, if possible, be so situated as to afford prompt mail
service. Telegraphic communication with the chief engineer
is important, though not always possible. Plans of all the
important structures on a division, excepting large bridges'-
are made at the division office and forwarded to the chief
engineer for approval. The monthly estimates made by the
resident engineers of his division are inspected by the divi-
sion engineer, a careful record of them kept at his office,
and forwarded by him to the chief engineer for approval.


1456. The Resident Engineer, His Corps, and
Their Duties. The corps in charge of eacfi residency,
comprises the resident engineer, instrument man, rodman,
tapeman, and axman. The resident engineer has immediate
charge of all work on his residency, a profile of which is
given him with the grade lines drawn upon it, with the
gradients and compensation for curvature clearly stated.

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