16.06.15 Pt. 649.8m (SH
660 452)
Pt. 649.8m (SH 660 452) |
Thankfully John set a
steady pace as we left the confines of Cwm Croesor and walked up the track to
the old disused Croesor Quarry. Our
destination was a hill that until 1998 had not appeared in any list, this was
soon rectified when I spotted it whilst on a walk around the Moelwynion, a few
minutes later I had surveyed it with my old staff and found that it had
approximately 50ft (15.2m) of rise from its critical bwlch to the high point of
the rock on its summit. This hill was
then duly surveyed by Dewi Jones, Joe and Tara Nuttall and finally John and
Anne Nuttall. During this time I also
surveyed it on two other occasions. It
was duly added to the Nuttalls list under the invented name of Moelwyn Mawr
North Ridge Top. This is not a name I
would advocate as research conducted locally will give a name to it, as will
historical research, but these more appropriate names will have to wait for
another day when the book that Aled and I hope to produce is published, or when
the Ordnance Survey apply an appropriate name to this and other hills that are
currently unnamed on their maps.
With one of my old measuring staffs at the summit of Pt. 649.8m |
Heading up the track toward the abandoned Croesor Quarry |
With John setting a
reasonable pace it meant that I could keep up with him and Graham, but I was
still unable to talk much of the way and did a lot of huffing and puffing. The blue sky of this morning had been quickly
replaced with cloud that pushed its way westward and blew across Cnicht, which
looked dramatically large with its steep scree laden south-eastern flank
showing itself below the enveloping mist.
The cloud enshrouded Cnicht |
The track we were on led
to the abandoned Croesor Quarry, what is on view is a tiny part of this once
thriving quarry, as its main operation and link to the nearby Rhosydd Quarry
was underground and once functional.
Before leaving the track and heading up to our hill, Graham had a look
into the entrance to the underground workings, this gave me time to rest and
get my breath back as although the mist and cloud skimmed across the hills
indicating that conditions on top would be a bit blowy, the warmth of mid-June
was pervading our ascent and copious amounts of sweat was bubbling from my
forehead.
Nearing the abandoned Croesor Quarry |
Leaving the track and
abandoned quarry we picked up the continuation of a path up the hill which soon
turned to a sheep track, at this point we branched uphill direct for our
surveying objective which loomed ahead showing its steep rock strewn southern
side. All around the higher hills were
obscured as the cloud enveloped the land and by the time we had reached our
objective the wind blew and the murk descended.
Leaving the track a vehicle path on the open hillside soon gave way to a sheep track |
Graham heading for the summit |
Within a few minutes we
had all put on extra layers of clothing as we planned on being on the hill for
a number of hours as we were going to line survey it and get GPS data from its
summit and bwlch.
We started at the summit
and pinpointed the highest part of the summit rock, we then took the equipment
down to the bwlch and each one of us in turn estimated where we thought the
critical bwlch lay and placed a yellow flag in our chosen spot. We then placed a number of flags at intervals
across the area of the bwlch in a valley to valley and a hill to hill
direction. By using a level and staff we
then narrowed the area of the critical bwlch down to a square metre, and once
we had taken readings within this small space of land the critical bwlch had
been found, and hay presto my yellow flag was proudly flapping in the wind on
it – YYIIIIPPPPPP!!!!!! Mind you John’s
estimation of where the critical bwlch lay was only 3mm in height different to
its actual position, but Graham was way off and had positioned his flag about
1.5 metres away in distance from the position of the critical bwlch and a few
centimetres higher than it.
The view from the summit as Graham pinpoints the highest rock |
Once the bwlch had been
found we inserted a surveyor’s bolt in the ground with a spare lace around its
base to help us get it back out of the ground.
We could now start the line survey with Graham operating the level, John
in charge of noting the readings and me operating the staff. As we proceeded up the hill it got chillier
and chillier and the mist blew across the bwlch with large gaps occasionally
appearing showing rising land toward Moelwyn Mawr and the great carved out gash
between us and the shapely profile of Moel yr Hydd.
John doing the sums |
The shapely profile of Moel yr Hydd |
Bit by bit we made
progress with John giving a running total of overall ascent, as we got nearer
the summit we all thought that the running total was indicating that this hill
did not have sufficient rise to qualify it for a P15 list. As the last reading took place with me
perched on top of the summit rock, John did the calculations and said that it
had only got 14.768m of drop, it had failed – oh bum! I wonder what John and Anne are going to
think about this?
Although Graham had
failed miserably to pinpoint the bwlch having been all of 1.5 metres from the
designated point, he succeeded in being the closest in his estimation of the
hill’s drop value, both he and John estimated that the hill did not have the
required 15m of drop, whilst I failed miserably with my estimation as I had
guessed a drop value of 15.05m.
So this hill is now
relegated to the ranks of sub-P15s, but it is still a worthwhile expedition,
similar in some ways to Knight’s Peak, albeit a bit lower in elevation and not
quite as buttock clenching to get to its summit!
We now wanted a closing
error so we repeated the line survey but this time back down from summit to
bwlch, this came to 14.765m, which gave a closing error of 3mm, this result is
extremely good.
With the line survey
completed John and Graham headed back to the summit to position the Leica GS15
over the summit block, whilst I set the Trimble up at the bwlch to gather five
minutes of data. Once the Trimble had
done its stuff I rejoined my two surveying comrades and we huddled down just
below the summit rocks in a well sheltered spot. Much of the next hour was spent chatting
about hill related subjects, as time progressed I lay flat with the curvature
of the ground fitting snugly against my back and I could have easily dropped
off to sleep. As I occasionally opened
my eyes and peered up I could see the orb of the sun peering back down through
the mass of swirling cloud, this would be quickly vanquished as the grey cloud
mass accelerated its western journey and we would be plunged back into mist.
Gathering data at the critical bwlch with the Trimble, whilst John and Graham position the Leica GS15 over the summit |
Graham and John beside the Leica GS15 at the summit |
After an hours data had
been collected by the Leica GS15 John and Graham took it down to the bwlch and
set it up over the surveyor’s bolt whilst I positioned the Trimble on the high
point of the hill and gathered five minutes of data, once the Trimble was
packed away I descended to another sheltered spot and joined John and Graham
for another hour’s wait.
Gathering data at the summit with the Trimble |
The hours wait seemed to
go quickly as more hilly related chat was had, and soon it was time to pack up,
strip off the extra layers of clothing for the descent and to retrace our steps
back down the hill.
The Leica GS15 set-up position at the bwlch |
Survey Result:
Pt. 649.8m
Summit Height: 649.7m (converted to OSGM15, Trimble GeoXH 6000)
649.8m (converted to OSGM15, Leica GS15)
649.8m (converted to OSGM15, Leica GS15)
Summit Grid Reference: SH 66096 45255
Bwlch Height: 634.8m (converted to OSGM15, Trimble GeoXH 6000) 635.0m
(converted to OSGM15, Leica GS15)
(converted to OSGM15, Leica GS15)
Bwlch Grid Reference: SH 66085 45195
Drop: 14.9m (Trimble GeoXH 6000) 14.8m (Leica GS15) Line Survey
(14.8m)
(Uchaf reclassification to 500m Sub-Uchaf and Nuttall deletion)
Dominance: 2.27% (based on Leica GS15 summit height and line survey for
drop)
(Uchaf reclassification to 500m Sub-Uchaf and Nuttall deletion)
Dominance: 2.27% (based on Leica GS15 summit height and line survey for
drop)
For further details please
consult the Trimble survey spreadsheet click {here}
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