Windham County reformer. (Brattleboro, Vt.) 1901-1906, 1902-04-04
Compass Variation and Its Effect on Land
Surveys.
Newfane, March %, 1902.
Editor of the Reformer:

|
Newfane, March %, 1902
Editor of the Reformer:
/ am often asked why the compass
needle points west of due north, anC
why variation is constantly increasing.
The generally accepted explanation OF
the first query is that there is mag
netc pole located a few hundred miles
south of the north pole which attracts
the needle to that point. If that were
true, the needle would point due north
at all places in line running directly
south from the supposed magnetic
pole, and the variation would be uni
form at all places of equal distance
from the meridian of no variation, and
all isogenic lines would be straight
and stationary, with no variation of
the needle from time to time. All ex
perience and observation shows that
the course of the needle has been NOV
ing west at an average rate of one de-
gree iu about thirteen years for the
last ninety years, and for 125
years previously it moved the other
way at nearly the same rate; and also
that it points from one-fourth to one
twentieth part of a degree more west
erly at o'clock in the afternoon than
it does in the morning of each day. 1t
is impossible to believe that magnet
ic substance of sufficient capacity to
attract the needle from all points of
the earth is constantly moving back
and forth, which must be the case if
that is what governs the needle; either
the magnetic pole is a myth or there is
some opposing force of vacillating char
acter that partially overcomes the eff
feet of polar attraction and is reSpon-
sible for the lack of uniformity in land
surveys. 1t was the intention to have
the boundary line between Massachu
sets and Vermont run due west from
the southwest corner of New Hamp
shire, the surveyor being instructed to
allow 10 degrees for magnetic varia
tions; presuming the line from the
river to the Leyden or Borden" col
ner was so run, the variation was then
about Z degrees 81 minutes and the al
lowance made about two and one-sixth
degrees too much as the line bears that
much north of due west. From Ley
den corner west the crooks in the old
line were too numerous to mention.
The present line runs as near due west
as possible without changing any of
Jllt HUH tllC Jul iSdlCllob
of Massachusetts to that of Vermont
but the line recently established by
runs four different
courses, making crooks at Leyden,
Phillips and Jillson corners and strik
ing the west line of the state over a
mile farther north than if running due
west. The original town and range
lines were accurately surveyed by the
compass, but owing to the daily varia-
ton of the needle and errors in mark |
ing, crooks of one-half a degree and |
less are quite common in the original !
lines, and as the surveys of towns were |
not completed at one time but extend
over period of 30 or 40 years the lines |
Of the last divisions of the allotments !
vary two degrees from those first made /
in he earliest settled parts of the |
towns. Subsequent surveyors made no |
account of magnetic variation until the /
office of county surveyor was abolished;
apparently the next generation of sur
1eyors tried to run lines partly by com
pass and partly by old line marks,
starting off as the course was given i'll
he deed and when finding they were
,ut of the line changing the course so
Is to come out right at the next cor
Ter: though occasionally one had the
courage to condemn the old line and
wear by his compass. 1t is sometimes
laimed that it is the surveyors duty to
ectify errors of former surveys but
hey lose sight of the fact that what
las been understood to be the line and
cquiesced in for 10 years becomes the +
egal boundary.
c. Z. Skinner.