Dip Needle or Miner's Compass
Brooke Clarke, N6GCE,
2003 - 2020
Aqua Locator related Patents
These are known as "Dip Needles"
or "Dip CIrcles" (Wiki
Miner's Compass where Strike and Dip (Wiki
are as important as bearing.
Reading water meters is made more difficult in that some are
not read frequently and so they get hidden by weeds, dirt
blown by the wind, etc. In order to make finding them
easier a number of products were developed, the Aqua Locator
is one of them. This product is not a "water witching"
device but rather a magnetic dip needle that's optimized for
locating ferrous metal in the ground, like a water meter, but
can be used for finding any ferrous metal that's relatively
near the surface. It's a compass that works on the
up-down part of the field (which is stronger than the
horizontal field in most of North America).
This is a magnetic dip meter.
Most water meters (Wiki
contain magnets that allow coupling the movement of the vanes
to the counting mechanism that's in an adjacent water proof
When the instrument is turned face
up it acts like a conventional azimuth compass, except the window
only displays the cardinal directions NW - N - NE, but by turning
the case you can get the Red end of the needle to point
North. Then the Aqua Locator is held a few inches off the
ground using the carry strap and is oriented with the North arrow
on the case pointing North.
Now maintaining the North direction slowly move the locator over
the area where ferrous metal might be located and look down at the
image of the needle in the 45 degree mirror. When over
ferrous metal the needle will move to a vertical position.
When I brought the locator over a metal stake that was driven into
the ground with a sledge hammer the needle flipped over, i.e.
instead of seeing the Red end the Black end was pointing up!
The stake probably was made into a magnet when pounded into the
ground. Or may have been manufactured as a magnet for just this
Sam Poon was kind enough to send the
instructions and here they are (less an image of the locator):
for use of the
The following is a series
of steps in the use of the Aqua Magnetic Locator. Please follow
them carefully for 100% satisfaction:
1. Open flap on leather
case. (Instrument need not be removed from case.) Turn AQUA
on its side, bottom of case toward you, NW, N, NE dial
level. In this position, your
AQUA is a
compass. Point dial portion north until red end of needle points exactly at
"N". You now have true north position.
2. Turn AQUA upright, point
gold arrow on leather case to "N", as was indicated
by instrument in step #1. (When leather case is very new,
it is helpful to fold
the flap down firmly so that it will remain in position
when in use, and not
obscure the dial.) Using carrying strap, lower instrument
to just a few inches
above ground, holding instrument carrying strap over four
fingers. Holding strap
by four fingers minimizes chances of instrument twisting
out of position as
you walk. Be sure that "N" is still pointing north.
3. Begin "walking" the
instrument in parallel paths, about 12 to 15 inches apart,
red end of the needle dips and the black end of the needle
Find the point of maximum reading: that point at which
black end comes nearest
to "90" mark. At this point, walk at right angle to
former path, still keeping
instrument pointing toward north, until maximum reading
is found on right angle
path. This is the location of missing valve box or stake.
When object to be located
is very deep in the ground, or heavily covered, a full
to "90" mark cannot be
expected. In cases of this kind, "70" or "75" may be the best
In areas where there are
high voltage overhead wires, there is usually electrical disturbance,
which will cause the red end of the needle to show on dial. This
does not hamper location operations. When over the object, red
end will disappear and black end will appear on dial.
Where shrubbery or other
obstructions prevent the strap method of holding instrument,
AQUA may be removed from its leather case and metal rim pulled
up and used as a
handle. However, whenever
possible, keep AQUA in leather case, as a protection
against possible damage
from bumps and jolts.
THE AQUA SURVEY & INSTRUMENT CO.
7041-43 VINE STREET AT SEYMOUR
CINCINNATI, OHIO 45216 PHONE: (513) 821-2514
AQUA MAGNETIC LOCATOR
LOCATES VALVE BOXES,
SURVEYOR'S STAKES, MANHOLE COVERS
OTHER CONCENTRATED FERROUS METAL OBJECTS.
Dec. 25, 1956, Christmas day the
patent office must have been working, US patent number 2775736
was granted with the assignee Aqua Survey & Instrument
company, Cincinnati, Ohio. the patent classes are: 324/260
33/345; 33/348; 116/303; 324/67; 324/156; 324/228; 324/326
Valve locating device, Othmar
Carl F Evert
Survey & Instr Co
, 1956-12-25, -
Latitude indicator for aircraft, George
, 1927-08-16, - used a magnetic needle
The body is about 3-1/2" diameter. As received the needle
was out of it's bearings. The cover glasses on both sides
can easily be removed to access the pivots'. There is a
shipping stability Split pin (Wiki) that
can be inserted on either side near the top which captures the
needle making it less likley to be jarred out of the
pivots. Note in Fig 2 I have the split pin in the
In Fig 2 and Fig 3 you can see a small spring near the pivots
on the white painted part of the needle. This can be moved
along the needle. These are common on normal magnetic
compasses and used to counter balance the downward force on one
end of the needle so that the needle sits level. Without
this feature on a magnetic compass the needle tends to jam or
have high friction and so is sticky. But I don't see why
this weight/spring is on a dip needle. Let me know why it's there.
Looking for WS Darley
& Co but no Dip Needle patent found, but many pumps.
Improvement in compasses for mining, J. Blomgren, Oct, 25, 1870, 33/355R; 324/259 -
Dipping needle, Pascal H Stedman, 1908-05-12, -
Prospector's needle, Dell W
Jewell, 1910-06-14, -
Instrument for geophysical exploration, Zuschlag
Theodore, 1949-02-15, -
Magnetic instrument, Boepple
Otto Hartwig, Kenyon
Inst Co, 1964-07-28, -
3 Axis Magnetometer - field
Aircraft Pilot's Standby
Magnetic Compass B-16
DC Gaussmeter Model 1
AMY6 Magnetic Polarity Tester
GE Gauss Meter & Reference
Fluxgate (& other) Patents
Research Instrument Co. Fluxmeter
Scientific 79860 Dynamo Analysis Apparatus - works with Fluxmeter
M3 Coil Magnetic Survey
Home Built Magnetometers
HP 428 Clip-on Milliammeter
HT20 2000 mT Magnetic Flux Meter
KVHC100FG KVH C100 Flux
Gate Compass module
Magnetic Compass Calibration Set similar to AN/ASM-344
Magnet DC Motors
Equipment, Stock Ticker, District Telegraph, Teletype, Keys,
Relays, Sounders, Veedre Counter, Early Connectors,
Torpedoes tried to use
Weeden-El-Mtr Weeden DC Electro0magnetic
Machine (Motor or Generator)Wireless Driveway Monitor - STI-34100
solar power magnetometer
Kenyon College, Ohio - Instruments
for Natural Philosophy - Electricity
Dip Needle - a page of photos of old ones.
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page created 5 July 2003.