Powerful
Chemical Conundrums
This series of progressively more complicated mystery caches is
based in southern Tasmania. A feature of the series is that no
waypoint is available for any of the caches. Each cache is located
near an electrical distribution pole or tower ("Powerful").
Transend operates Tasmania's 220 kV and 110 kV transmission
networks and our interest is in their high voltage transmission
towers. Aurora Energy distributes electricity using a lower voltage
network utilising power poles. Safety note: follow any safety
warnings and avoid climbing or interfering with the structures.
Finding each cache involves four parts:
- To find the coordinates of the power or tower you will need to
solve puzzles based on chemistry ("Chemical Conundrums"). For
example properties of a chemical element or of a chemical compound
might be used. (Wikipedia is an invaluable tool for
this.)
- Each pole or tower targeted can usually be reached via a 0.5 -
5 km walk (or bike ride) along the associated service road
(typically of 4-wheel drive standard). There may also be an
alternative, sometimes shorter, walking track. You could use Google
Maps or Google Earth to plan your route (see Tip 1 below).
Coordinates may be confirmed with Geochecker (www.geocaching.com).
(see Tip 2 below).
- Once the site has been reached a further short walk, sometimes
through light bush, will be required to get to the "waypointless"
cache. Each pole or tower has an identifying label attached to it.
You will require this information to solve a puzzle to discover
where the cache is relative to the pole or tower. Typically you
will need to determine distances and/or bearings. It is this part
that becomes more difficult as the series develops.
- Use the information revealed in Part 3 and find the actual
cache. Since poles and towers are very conspicuous and easy to
find, locating the cache has been made more challenging. The cache
is in a screw top plastic jar in a black bag and is hidden so as to
be inconspicuous. It contains a few small swaps and a couple of
items donated by the School of Chemistry, UTAS.
Please note that all coordinates, distances and bearings are as
reported by a GPS receiver at the site. The calculation of
distances assumes a spherical earth and are great-circle distances;
local terrain is not taken into account. Bearings are true and
measured in degrees. (Some GPSRs do not measure bearings
sufficiently accurately. You may therefore need to use a magnetic
compass for the bearings but remember to allow for magnetic
variation, currently about 14° E. Note that a magnetic compass is
less reliable when in close proximity to high-tension power lines.)
Now for this particular cache - good luck with the puzzling,
walking/pedalling and finding.
POWERFUL
CHEMICAL CONUNDRUM 06 - East Risdon Nature Reserve
No waypoint is available for the cache, it has to be found by other
means. Therefore more advanced techniques than just going to the
cache's waypoint are needed. (As a bonus this provides an
opportunity to practice navigation skills.)
GPS techniques used to find this cache:
- Locate an object using its coordinates (waypoint)
- Make waypoint(s)
- Determine distances and bearings
- Locate an object using a bearing and distance from a point
Part 1
The cache is not at the listed
coordinates. The required transmission tower is at
S 42° 49.x and E 147° 19.y where x and y are
both three digit integers. This puzzle involves properties of the
element zinc (due to the nearby Nyrstar Zinc Smelter).
- x = (1 + a)2 where
- a is the atomic number of zinc. (The atomic number of an
element is the number of protons in the nucleus of an atom of that
element.)
- y = (100 * b) + c + ( 3 * d) where
- b is the integer part of the density of zinc.
- c is the integer part of atomic weight of zinc. (The atomic
weight of an element is the average mass of an atom of an element,
where the average is weighted to allow for all naturally occurring
isotopes of that element.)
- d is the number of naturally occurring isotopes of zinc.
(Isotopes are atoms of the same element which differ in the number
of neutrons they contain.)
Coordinates may be confirmed (see Tip 2 below).
Part 2
Next you need to determine how to get to the tower positioned at
the coordinates discovered in Part 1. You can view the location in
Google Maps and/or Google Earth (see Tip 1 below). There may be
several alternative routes.
Site notes: The towers and cache are located in a nature
reserve. The reserve contains rare trees and all fauna and flora
are protected. Dogs are not allowed.
Probably the best access route is via the Shag Bay Heritage Trail
(highlighting Aboriginal heritage sites). Walking is
recommended.
Part 3
Let us call the transmission tower that you have just located
"Tower A". Identify another transmission tower that is Tower A's
closest neighbour and call this "Tower B". Tower A has a label
"Transend ghiTj" where g, h, i, j in "ghiTj" is each a digit in the
range 0-9.
Consider a straight line joining the centres of the bases of the
two towers - "Line A".
- m = length of Line A (metres)
Now consider the straight line ("Line B") that is the perpendicular
bisector of Line A. The cache is on Line B and is n metres from the
centre of Line A. Although by symmetry there are two possible sites
for the cache, the cache is actually in the NW quadrant. Visibility
is somewhat restricted due to the vegetation.
A diagram showing the cache location is available - see
below.
Please note that there is a compounding of errors
(uncertainties) here so "cast your net wide". The cache has an
arboreal association.
Part 4
Follow the directions in Part 3 and find the cache. It is a screw
top plastic jar in a black bag and is hidden so as to be
inconspicuous; it may take some time to find. The jar contains a
few small swaps and a couple of items donated by the School of
Chemistry, UTAS.
Tip 1 - Visualising the location (optional)
The site coordinates can be used in Google Maps
(http://maps.google.com.au/) or in Google Earth (if installed) to
visualise the location so that you can determine your approach.
Prescribed formats are needed. An example follows. (The result
should show the location of Junction Cabin.)
Suppose the required location is S 42° 53.253'
E 147° 15.150' (in geocaching representation).
For Google Maps or Google Earth use location:
42 53.253 S 147 15.150 E or location:
-42 53.253 147 15.150
Tip 2 - Confirming coordinates (optional)
You can check your answers for this puzzle on
Geochecker.com.(a location map is also displayed).