The Seattle post-intelligencer. [volume] (Seattle, Wash. Terr. [Wash.]) 1888-1914, 1890-06-30
UNITING THE ROUTE.
,..hlems Which Confront the
Railroad Surveyors.
~ QUESTION OF GRADES.
.t Amount Of Expensive Work
sesessary Before shoveisui
OF Dirt Is Thrown.

OF Dirt Is Thrown.
r.rv few pcrsons outside OF the ranks OF
-.;ssers and practical Observation-Disclosures
- sny adequate idea OF the amount OF
-ssrsive york which has to be done be-
s "a - scf,1ai construction of road is
ss'ss - Lofty bridges. long tunnels,
- excavations and other tangible results
80 ,shk,r of thousands OF strong arms
- heir own tale OF the outlay OF money.
~ = regards the process of choosing the
=, ,o<ifion for the line, there seems TO be
- General impression that it is some
.sirr ike repetition OF the experiences of
!. Roman general who came, saw. and
.-.rr.me.n How wide of the truth this
IS, ! II is proposed to show in the follow
- .ketch OF the methods employed by
ss g engineers. Brief and cursory as
- descriptions must necessarily be. We
- that an explanation OF this subject.
E..etsd AZ far as possible of all technical
s,ms will be OF interest not merely 10 those
,soassnds OF tourists in whose quest OF
,...,ure the iron track is just now such an
ssrntial factor. but also to business men
rbo contemplate putting their capital into
always.
When q line is projected between two
,aints the FIRST step Is to make recon
.a;sssnce. . that is, arapid inspection OF the
aseryening country for the purposes Of
.h,.ininc general idea of its characters
d This operation is, of course. more
!. les elaborate and exact according to the
,sture OF the region to be traversed. In
Ae San Joaquin valley, for instance, where
line can be run from anywhere to any
vhere With minimum of grading, re-
renaissance would be merely nominal.
IS tia other hand, il it is proposed to carry
- line over any OF the ranges which in
elose that valley, very careful examine
- At the various rivers penetrating the
,nmnfsins, and of the different passes
rSich are not too far from the direct route
Z e utilized, would be necessary. The
e.mparstive elevations of the passes being
smstser Of prime Importance, careful bar
sne.rical observations would be made
III view to ascertaining their approx
;rake heights Should these observations
m result very decidedly in favor of
- eass. it would be noted as point TO
v5iA the location of the line must con-
-. subject OF course TO the contingency
ahsng rejected for some other, the APP
Sreches to which may be so much easier
= i compensate for the greater height to
1urmouated. in practice, however,
GcAacase Is extremely rare, and the main
1Lsef az q reconnaissance of q great
,sontain range like the Sierra is achieved
4sen The lowest pass between the points
i y connected has been found.
Haline is to be built along great river.
suofher class of questions will come up for
unrideration. Both banks must be exam
hed With view not only TO economy in
mnsssuction, but also to the present condi-
ten Of traffic and its possible future devel-
enents. Will il be best to build on one
| he exclusively, or to cross over at certain
uints, and If so, where and how often?
fsese questions cannot be answered fully
/ urll d more detailed survey has been
nsds, but they must be carefully pondered
/ b he engineer on the reconnaissance. The
/ most troublesome cases of all, however, is
/ phe,e two distinct mountain ranges lie be-
meea the proposed termini. Here the
/ hxest parcels of each range may not be
0nrenently situated with regard to each
xher, and the problem may be yet further
duplicated BY the fact that in the inter-
ming valley there is some point, such as
t8ourishing town or suitable spot for
ridge, through which it is desired that the
heshoud run. A compromise between
he different routes indicated by such cir
tunstanees must in this instance be made,
md. unless the general character of that
wnpromise is de ernined by the recon-
asissance, much time and money will alter
rard he til rown away on running expert
ntntal lines.
The upshot OF this cursory inspection
vii Be that the engineer is able to say with
Ent confidence that the road will be
ncated in one OF two or three narrow strips
Gconntry. The next step, therefore, is to
Moaalt these TO a more minute examine
Toe By means of wnat is technically known
The preliminary survey" The basis
the survey is traverse" which is SIM
by zig-zag line measured along the strip
@gfound upon which il is supposed the
ncaaon will fall. To secure satisfactory
isa.ts, patience, attention, steadiness of
pad and activity are needed, and SO rare
Us The requisite combination of qualities
MUD that an engineer Of long experience,
Hao laid special stress upon the correct
measurement. once declared that he had
mroyed many excellent instruments
seh-but had scarcely ever come across
snnainan who came up to his standard.
VI late Years new method, called
s1d'a surveying" has been coming into
seus. The engineer having set his transit
aone point observes the space which two
parallel wires Inserted in the telescope in
Ncept upon graduated rod he'd by an
EAssant at the point the distance 10 which
so De estimated. That distance being
.tNiy In direct proportion to the space IN
k'eepted on the rod, il is evident that ii a
slssln space and certain distance are
n "A 4.
gay De estimated at once by a reference to
Me Standard. In practice. as the propor-
Mas not exact, some small corrections
Ensionsiy calculated. are applied. The adj
images OF this method are the saving OF
me and labor which it effects, and also
IS very important circumstance that the
ssaraey OF the measurements is thus
ssae 70 depend upon the transitman him.
a. In rosgh country where claiming
SOW and difficult, stadia surveying is
S non all doubt the best system.
49, = me The transi'man and his assistants
sssasaged as above described, two other
sases are occupied with ieveiing ana to-
rrE'apnicai work. The special duty of
ma sseler IS to find the elevations OF
s... snt number OF points along the ira
Tse Itself to enable him 10 draw a nrofile
I've surface. Most persons have some
- :. o. the meaning of this word as used
engineers, or at least its general APP
ssas'aace. which exactly resembles that of
nssaht mountain range when defined
1 lslspn.y sgainst the sky. Obviously, if the
s,.a OF all the peaks and depeessions of
a. 49, so seen above any fixed level-say
4. surface OF the sea--are known. and also
IA. aol'aontal distances between them,
d a. oasalne could be represented on paper
d IN. ssa.e mat might be chosen. This
zee. knowing from his own nrevious
49, sk or from other source tie elevation az
ssss. aAsd point, called bench mark. -
~. as Place where the traverse begins, is
shs, :" estimate the height of as many
h nses ms along the traverse itself as may