PLSO March April 2017

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Professional Land Surveyors of Oregon |
Lost & Found
word “dalle” meaning “sluice” or in “voyager french,”
referring to rapids or turbulent water, none of which
the Barlow company had seen as they paralleled the
comparatively docile Columbia River westward over
relatively gentle ground from its junction with the
Snake River. At The Dalles, both riverbanks steepened
drastically and soon rose to more than 2,000 feet
above the river with an impressive array of lava cliffs
and waterfalls, making further travel by wagons
impossible through what today is known as the
Columbia River Gorge. Most previous pioneers had
to dismantle their wagons and put them on hastily
built rafts to carry their families and possessions
downstream past the nearby “dalles” in the river and
on to the dreaded “cascades” where they would then
have to portage several miles to regain the relatively
placid waters below. Many preceding pioneer families
had lost either their possessions or their lives during
this forty-some mile long ordeal. Captain Sam Barlow
had heard about these perils over the past five
months on the trail and was determined to find a
route over the untried mountain passes instead. He
declared “God never made a mountain that he had
not made a place for some man to go over it or under
it. I am going to hunt for that place…” After much trial
and error, he and a companion, after numerous dead
ends and false starts, returned in late November to
retrieve his waiting company, now smaller, and begin
the traverse over the south side of Mt. Hood towards
Oregon City. After leaving their wagons enroute, most
of the party finally made it out of the snowy mountain
canyons on foot, two days before Christmas. They
later retrieved the wagons and completed their
journey to the fertile Willamette Valley. In 1846
Barlow made application to the Provisional
Government for a charter to open
a wagon road over the route
he pioneered the fall
before. It was
readily granted and the Barlow Toll Road was slowly
improved and started receiving travelers willing to
pay a toll versus the other alternatives. Today, its
old track can still be seen as it crosses the range
line several chains south of the northeast corner of
section 25. Its grade snakes along, climbing out of
Rock Creek to the east and reaches the rolling oak
and pine savannah near a wooden gate as it enters
Section 25. It was not hard for me to imagine Mr.
Edwards and Charles Ingalls ambling along a very
similar 1850’s road on their way to Mankato.
Our 1991 survey itself was a traditional traverse
using a “high-tech” Wild theodolite (for the time) that
contained a 3” square hard disc that recorded point
numbers, angles and distances (Code 10, Code 20,
Code 30, etc) and could then be ejected from the
instrument and put into an office “reader” that would
generate a hard-copy print. (An early predecessor
of the modern data collector.) I had also been using
an innovative sun-shot program developed and
marketed by Dr. Richard Elgin’s firm, Elgin, Knowles
and Senne, Inc. of Rolle, Missouri. I started using
it in about 1986 and found it to be a tremendous
improvement over the traditional method commonly
in use prior to that time (for most private surveyors
without a solar compass or solar transit). The “old
method” required measuring the vertical angle to
the sun and then going through a rather tedious
algebraic computation process involving ephemeris
data and local time and lat-long to derive an azimuth,
usually days later in the office. Another disadvantage
of the “vertical angle method” was that it couldn’t
be used reliably between about 10am and 2pm.
Richard Elgin’s program introduced the “hour-angle
method” to me and countless other surveyors. I
still use my HP-41CV with a “time module chip” and
Elgin’s “ASTRO*ROM2 chip” plugged in. I came to
prefer the “trailing edge” option and even now can
still come up with a true azimuth after about 10 to 15
minutes in the field. This was especially handy on the
1991 survey. I was always curious to know the “real
bearings” to BTs, etc. from the corner point (once it
was determined) to compare with the record
bearings of long ago. One only needed to occupy
said point and orient your instrument’s “circle”
to the true azimuth and then turn to the various
accessories and observe the actual true bearing and
measure the distance. On the 1991 survey, the BLM
had remonumented several corners along the range
line in 1965. When we set up on the east quarter
corner of Section 36, imagine my surprise when we
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