10.10.15
Bryn y Baal (SJ 259 647, to base of rock bluff)
Bryn y Baal and its rock bluff |
There’s nothing quite
like splitting a twin map heighted top, all the nonsense is then solved with no
more debate, however I quite like some of this nonsense and it would be a shame
to solve every twinned top problem as some should be left for future
generations.
I didn’t even now that
we were going for an early morning little twin topped adventure until I was in
the car with Mark and he was driving south-east from his house in Sychdyn. We’d driven past this spot before as this
little problem is one that Mr Trengove is particularly enthusiastic to
solve. On this previous occasion Mark explained
that Bryn y Baal is given a spot height of 172m on the Ordnance Survey enlarged
Geograph map and the high point of this hill is a rock bluff in the back garden
of quite a large house, whilst 1 km further south-east is another 172m high
point called Prenbrigog (SJ 266 640) which has its summit either at the back
of, or at the side of a farm house.
One small Trimble and one large house. I wonder if the occupant will give permission to survey the high point of their garden? |
Mark had investigated
the area below the large house at Bryn y Baal where until recently a high fence
festooned with ‘No Climbing’ signs had attempted to dissuade any P30 baggers
from a below the rock bluff approach, this approach is not recommended as a
rope would be required for all but the most competent of climber.
The area below the rock
bluff had recently been altered as there is now a two metre high chain link
fence with a gate and accompanying locked combination padlock, with the area
situated away from the immediate surrounds below the rock bluff now having a
local amenity area with a nature reserve and an information board. However, of most interest was where the spot
height appeared on the map, this was positioned at the bottom of the rock bluff
beside the fenced off area, if the height and position of this 172m spot height
proved correct, the summit of Bryn y Baal would be approximately 7m higher, and
if this was so, then Bryn y Baal would be the higher of the current twin tops. All that was needed was an accurate height
measurement taken to where the 172m spot height appears on the ground. Mark had already obtained a 168m reading at
this point with his hand-help GPS which consistently gives readings between +3m
- +5m above the actual height.
Confirmation was needed and as I tried to wake up in the passenger seat
and work out where we were going and why, we arrived, and Mark directed me
toward the base of the rock bluff and said ‘get the Trimble up and running as
we don’t have much time’. This statement
referred to our pre-arranged meeting with John Kirk in Sedbergh and if the
Trimble didn’t attain its 0.1m accuracy level quickly we would be late.
The surrounding land at the base of the rock bluff |
As I set the Trimble up
on top of my rucksack we discussed the height difference between the ground at
the base of my rucksack and the high point of the rock bluff and estimated this
to be 7m, with a margin of uncertainty for height difference to be +/- 1.5m.
It took the Trimble
about ten minutes for it to attain its 0.1m accuracy level and once it did I
pressed ‘Log’ and wandered around taking a few photographs of the scene. As the last of the 300 data points were
collected I pressed ‘Done’ and packed the equipment away and joined Mark beside
his car for our journey north to meet Mr Kirk.
Survey Result:
Bryn y Baal
Summit Height: 171.5m (converted to OSGM15) (approximate value from
164.5m survey to base of rock bluff)
164.5m survey to base of rock bluff)
Summit Grid Reference: SJ 25902 64765 (to base of rock bluff)
Drop: c 50m
Dominance: 29.16%
Dominance: 29.16%
For further details please
consult the Trimble survey spreadsheet click {here}
No comments:
Post a Comment