The gold leaf. [volume] (Henderson, N.C.) 1881-1911, 1898-04-07
THE EARTH'S MAGNETISM IN
NORTH CAROLINA.
How it Varies-A Magnetic Survey
Needed-NO Accurate Boundary
Lines Without tits Cost, &c.

The earth's magnetism is one OF those
mysterious forces in the world, the ma
TN. of which nobody has been able to
explain to the satisfaction OF other peo-
nile but like other Of these mysterious
forces man is making use of tin the prac
tical affairs of life through the magnetic
compass, the telegraph the telephone
and in many other ways. NO ship ven
lures upon the sea without magnetic
needle as it's guide 10 man attempts to
locate the boundary line OF a State
county, township, or an acre OF land,
without calling to his service TINS mys-
terious force of nature manifested IN the
compass of the surveyor. Hence 1t
deserves a careful Investigation
1t is we'll known that our little com
pass needle which indicates the magnetic
north does not generally point to the
true North pole, but usually niue 10
the east or to the west OF that point.
Hence. in ordinary surveyors language
we speak of the compass needle varying
SO many degrees to the east or the west
of the true north. % Furthermore 1t
is well known that the amount OF this
variation is quite different at different
places. Thus, in 1887 the following va
riations are approximately correct Tor
three different places in North Carolina:
Newbern degree and 54 minutes west;
Raleigh 1 degree and Is minutes west;
AsheviIe 81 minutes east.
9. And yet there are places where the
magnetic north agrees exactly with the
true north and south line, and such
would be spoken of as places OF no vari-
alton. But these points OF no variation
instead OF remaining stationary are III
North Carolina moving westward. mus,
in 1910 the line of no varlatlOh was az
Newbern; in 1866 at Raleigh, IN 1881
near Asheville. And this OF course lneaie
that the amount Of variation at one
place in North Carolina lnsteau OF re-
naming the same year after year is grad |
ually changing. Thus at Raleigh in |
1915 the variation of the magnetic line |
| from the true north was degrees, A |
| minutes east. In about 1866, as stated |
| above, the magnetic north and the true |
north were the same, and hence there |
| was no variation. Butin 1887 the mag
netic north moved to the west OF the
| true north to the extent OF l degree and
| IS minutes.
| g. Though the variations just men
toned are sufficiently puzzing to give
the engineers and land surveyors con-
| siderable amount of trouble, if the irreg
ularities named were all that we had to
contend with the difficulties could be
overcome with some ease, after locating
the true north and south line at few
stations, as at Newborn, Raleigh, Char
| lotte, Asheville, etc.
But, unfortunately, if starting on our
southern boundary line we follow the
compass needle across the Estate OF North
Carolina, we will find that instead OF
travelling in a straight line We would
| rrnhah lv mako nf considerable
magnitude in areas of even smaller ex-
tent than one of our counties. SO that
instead of the magnetic north and south
line across the State beinga straight line
it may be quite a crooked one. COnse-
quently a magnetic map Of North Caro-
lima showing the variation OF the COM
pass needle in the several counties OF the
State could not be prepared unless the
conditions had first been examined in
each of these counties.
HOW A MAGNETIC SURVEY CAN BE MADE
ITS COST.
That such magnetic survey should be
made at once no intelligent person who
is familiar with the records of our courts
and the difficulties of re- lOcating old
boundary lines can doubt for a moment.
| The question arises, how can this be
done; how much would it cost, and can
it be done at once. Let me say that the
first thing which ought to be done in the
making OF such a survey is that in each
county seat of the State the true north
and south line should be determined
with all possible care and marked by
stone posts, known as meridian posts, so
that at any time engineers and surveyors
working in that county can go to this
point, test their compasses, and the
variation at that time.
This, of itself, would eliminate many OF
the troubles that have arisen in the loca
ton of the boundary lines, but this Of it
| self would not be sufficient in all cases,
for the reason mentioned above that the
variation at the county seat would not
necessarily Indicate the amount of vari-
alton in more distant parts of the
county. Thus, if at Raleigh the varia-
ton should be degrees, and in the
southwestern corner of Wake county
this variation might only be one degree,
this difference of a degree in the varia
ton would in running a line one mile
long throw that line out nearly one hun
dred feet.
But difficulties of this sort can be large
~ eliminated il after the true north and
south line has been determined and
marked at all the county seats, a mag
netic map is drawn on which are indi-
Gated all the records thus obtained; and
if after this map is made any special va
ration in the magnetic lines are indi
Gated. special examinations can be made
in that reg ion in order to determine the
character and extent of these variations.
After this has been done the magnetic
map can then be revised and the lOca-
ton of the curved lines as well as the
straight lines can be indicated in each
county.
Then, there need only be made in the
future, at intervals, observations at a
few points like Newbern, Raleigh, Char
lotte and Ashevile to determine the
| rate of variation from year to year, but
this later work would be readily done by
the general government without cost to
the State
| COST OF A MAGNETIC SURVEY.
As to the cost OF magnetic survey
like the one outlined above, it is esti-
mated that about $50 per county will
bear all expenses connected with the
true north and south line, the determi-
nation of the strength of the magnetic
force, the existence of causes of local va
riations, and the erection of meridian
posts (of grantee.
This work should be undertaken in
North Carolina at once because, in the
first place it is something which is
greatly needed, and in the second place,
it can be done cheaper and better just
now than it could have been done at
any time in the past or than it could
probably be done at any time in the
near future, owing to the fact that dur