tasmanian heritage register datasheet - heritage.tas.gov.au hydraulic mine.pdfrainfall would flush...
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Tasmanian Heritage Register Datasheet
103 Macquarie Street (GPO Box 618) Hobart Tasmania 7001
Phone: 1300 850 332 (local call cost) Email: [email protected]
Web: www.heritage.tas.gov.au Name: Mayday Hydraulic Mine THR ID Number: 10674
Status: Provisionally Registered Municipality: Waratah-Wynyard Council
Tier: State
Location Addresses Title References Property Id144941/1 2710225 Guildford RD, Guildford 7321 TAS
Telescoping pipes and
the nozzle, Mayday
Hydraulic
Private collection
Rails, tailrace and
overburden, Mayday
Hydraulic
Private collection
Wooden fluming,
Mayday Hydraulic
Private collection
Telescoping pipes
downslope, Mayday
Hydraulic
Private collection
Divide in a water race,
Mayday Hydraulic
Private collection
Setting: The Mayday Hydraulic Mine is on a tributary of the Mackintosh River, part of the Pieman River system, in
the highlands of north-western Tasmania. The mine and most of its water race system are located in
regrowth scrub (including bauera, horizontal and dogwood) resulting from the falling of timber and burning of
the area in the days of the mining operation, but just above the workings a stand of mature myrtle rainforest
extends along the western side of a creek. This creek, red with tannin, cascades through the mine site on
its descent towards the Mackintosh River.
Description: The former mine site consists of several water races surveyed to a uniform grade in order to facilitate a
constant flow, the site of a holding tank, the remains of wooden flumes, the remains of a set of telescoping
iron pipes which brought the water at high pressure down to the mine face, metalwork associated with
playing the hose onto the mine face (the canvas nozzle is missing), the sluiced mine face itself with trial
adits, a channel which held the sluice boxes, a pile of stacked rocks (mullock or overburden), a stack of iron
rails perhaps never used at the mine and other relics, including a perforated metal plate possibly out of a
sluice box. A creek served as the mine’s tail race, in which tailings were discarded (the creek bears little
evidence of siltation, perhaps because comparatively little mining work was done and because the highland
rainfall would flush out the creek every winter). The chimney butt of at least one hut site can be found along
one of the water races; a refuse scatter marks the probable site of another hut; other potential hut sites have
been identified near the pipeline. While mining here was short lived, the area was hunted regularly, and huts
may have been reused for that purpose. There is a series of exploratory trenches along the eastern side Wednesday, July 10, 2019 Page 1 of 6
of the creek below the mine site.
One water race taps the upper Leven River, bringing water across the divide to the Pieman River system.
Given the reliance on gravity to move the water, a tortuous route had to be found around the high ground
between these water systems in order to maintain the necessary downward grade, demonstrating
considerable surveying skill. As it approached the creek, the Leven River race was divided in order that
some water could serve minor workings. The main part of the race continued to the main workings. Another
race taps the creek itself above the mine. The Leven River and the creek races come together at the site of
a now missing holding tank high above the mine site, from which the telescoping pipes brought the water at
high pressure to the face. A nearby road and power lines with their associated firebreak cut through the
Leven River water race.
The site of this mine, with its rotting extant woodwork, appears to have escaped fire for more than a century.
It is within 50 metres of an area where myrtles have recently been felled, possibly for firewood, and is
vulnerable to vandalism, fire and pilfering.
History: The Van Diemen’s Land Company (VDL Co), established in London in 1824 to grow fine wool in Van
Diemen’s Land, was unlucky in its land selection. Its major holding, the 150,000-acre Surrey Hills block in
the northwest of the island, was just outside the rich Mount Read Volcanics zone and the tin -rich Mount
Bischoff granite, and was capped with basalt which obstructed mineral prospecting (Montgomery 1895). The
VDL Co’s subsidiary company, the Van Diemen’s Land Mineral Company, failed to find valuable minerals on
its land in the years 1882–92 (VDM1/1/1 and VDM2/1/1). However, for years the company’s prospector WR
Bell scratched away at mineralisation just outside VDL Co land, on the edge of the rich scheelite and
magnetite skarn deposit which only in the twentieth century was opened up as the Kara mine. Similarly,
modern exploration techniques revealed the valuable Hellyer ore body opened up in 1989 in the Mount Read
Volcanic belt only four kilometres south of the Surrey Hills block . The company was destined to not profit
directly from mining.
Occasional discoveries of alluvial gold were made along the western edge of the Black Bluff Range from the
1850s without a gold reef being discovered. In May 1895 the VDL Co’s prospector WR Bell reported that
gold had been found on the VDL Co's Surrey Hills block, adding to the list of tantalising discoveries (Bell
1895).
The economic climate was right for gold mining. Because the price of gold was fixed, people turned to it as
a safe haven during times of economic depression when currencies and commodities often lost value.
Prospectors renewed their search for gold, and old gold mines were reworked at such times. It is no
coincidence that Tasmania’s gold production increased markedly after the economic crash of October 1891
(from 23,451 oz in 1890 to 51,165 in 1895) and during the Great Depression following the Wall Street Crash
of October 1929 (from 5897 oz in 1929 to 17,600 in 1936). The mid-1890 s were also the time of the Western
Australian gold rushes, when Coolgardie, Kalgoorlie and the Kimberley became household names across
the Australian colonies. Gold ‘saved’ Australia during economic depression, as countless thousands of
people journeyed westward looking for work, wiring money back to families in the eastern states (Blainey
2003, pp.185–86, 193–94). However, anxiety about their economic security also made people more
vulnerable to gold-inspired ‘get rich quick’ schemes.
Hydraulic sluicing, a mining technique which was popularized at the Californian gold rushes after its
introduction there in 1852 (Greever 1963, pp.50 and 54), came into vogue in Tasmania two decades later for
tin mining. It provided a means of working poorer mineral-bearing ground economically and of attacking deep
leads (that is, mineral-bearing, buried former river beds). Hydraulic sluicing relied upon being able to bring
water to the mine face at high pressure in order to blast away the mineral-bearing rock. Usually races
carried the water to a holding tank above the face, from which narrowing (telescoping) pipes concentrated
the pressure on the steep fall down to the mining face. A canvas nozzle or monitor concentrated the water
further, blasting the face with a jet of water like a firehose. Lumps of mineral-bearing rock were washed into
sluice boxes, the heavier mineral settling in the riffles of the boxes, while the lighter dirt was washed out
through a tailrace. Although the infrastructure needed for hydraulic sluicing was expensive to install, labour
costs were afterwards minimal. One man manipulating the hose effectively replaced many armed with pick
and shovel (Idriess 1979, pp.112–48).
Tasmanian tin miners used this technology from the 1870s but until the 1890s no legal provision had been
made for its use in gold mining. Hydraulic sluicing was simply not viable within a 20-acre lease normally
issued for hard rock gold mining. Large scale mining was needed to offset low grades and the expense of
headrace and tailrace construction. In June 1893 the proponents of Tasmania’s first hydraulic gold mining
operation the Salisbury and Beaconsfield Company persuaded Minister of Mines William Hartnoll to
suspend the lease provisions of the Mining Act (1893) and withdraw 1000 acres at the Blue Tier near
Beaconsfield for ‘a limited period’ for its use (‘A mining deputation’ 1893).
It was at this mine that wheeler-and-dealer Rudolph Wachsmuth, a potato-growing, piano-tuning,
Wednesday, July 10, 2019 Page 2 of 6
violin-playing former engineer in the Prussian Army, set the model for the hydraulic gold boom that followed
(advert 1878; ‘A merry party’ 1892; ‘From Paradise to Beulah’ 1893). Wachsmuth mined gold in four
colonies, although it is unknown whether he was ever successful ( ‘Items of news’ 1873; ‘Sluicing the
Bendigo Creek’ 1893; ‘Sweet Marie’ 1896). Utilising Victorian capital and his own experience of hydraulic
sluicing on the Otago goldfields in New Zealand, he recruited a suitable mine manager and an assistant
across the Tasman (‘Social gathering at Tuapeka West’ 1891; ‘Mining news’ 1891; ‘Mining notes’ 1893;
‘Mining notes’ 1894; ‘The Rise and Shine Co’s Claim, Pomahoka’ 1892; ‘Hydraulic sluicing in Tasmania’
1892; ‘Hydraulic sluicing in Tasmania’ 1894). Over the next few years, Otago ‘hydraulicers’, miners recruited
by Wachsmuth and others, would find as much demand in Tasmania as Cornish mine managers had done
during the Heemskirk hard rock tin boom of the previous decade.
The Salisbury and Beaconsfield Hydraulic Co. was a failure, but by then Wachsmuth and fellow speculator
Robert Symmons had turned their attention to other abandoned goldfields. Following a favourable report on
the potential for hydraulic sluicing on the Pieman River goldfield by Government Geological Surveyor
Alexander Montgomery, formerly director of the School of Mines at Thames, New Zealand, they obtained
further extended leases there (Montgomery 1894, p.11; ‘House of Assembly’ 1894; ‘Death of a Tasmanian
geologist’ 1899). At least thirteen hydraulic companies, mostly with New Zealand managers and registered
in Launceston, were established in the district as a result.
The Pieman River hydraulic field was on the slide after June 1895, when the Corinna and Brookside
Hydraulics cleaned up their sluice boxes, returning only 80 and 34 oz of gold respectively ( ‘Mining’ 1895).
Confidence in the field plummeted, some mines being abandoned instantly. It became apparent that,
although hydraulic sluicing had been highly successful on the Otago goldfields, there were two reasons why
it did not work at the Pieman River: the high elevation of many of the terraces made it difficult to supply them
with high-pressure water; and the comparatively small amount of gravel available to sluice made the process
uneconomical (Thornily 1897, p.55).
Whether the same problems applied on other small Tasmanian goldfields remained to be seen . Wachsmuth
and Symmons had examined the gold deposit on the Surrey Hills, and in October 1895 the Mayday Gold
Mining Company, No Liability, was registered in Launceston, the shareholders including well-known mining
investors such as the solicitor and wool-grower Frederick William Grubb (advert 1895). The VDL Co did not
own the mineral rights to its land, so simply became an interested spectator in the development in the
south-eastern corner of its Surrey Hills block.
Spruiking of a hydraulic gold mine usually involved regular press reports about the development of the highly
efficient infrastructure and the growing anticipation of healthy returns . This would be followed by silence
which denoted a very disappointing clean-up of the sluice boxes. Perhaps the failure of the Pieman hydraulic
mines had muted even the promoters’ enthusiasm because the Mayday Hydraulic operated almost
anonymously from the start, with just one two-line progress report: ‘Simmons and Wacksmuth’s [sic] party,
working at the Mayday, likely to be a big thing’ (‘Black Bluff’ 1895). The paid-up capital of only £1000 must
have been exhausted by survey work and race building. Two calls were made on shares in the Mayday Gold
Mining Company by December 1895 (advert 1896), after which time the company disappeared from the
newspapers.
Like its predecessors, the mine is said to have been abandoned after the first clean-up of the sluice boxes
(‘Gold at Mayday’ 1911). Reporting on the mine again to the VDL Co in May 1896, WR Bell wrote that
treatment of several hundred tons of material returned little more than traces of gold, suggesting that the
good assays which prompted the work were obtained from a more recent, superficial deposit of limited
extent (Bell 1896). The site was added to the list of mining failures on VDL Co land.
Although situated in the highlands, the Mayday claim was accessible. By 1897 the extension of the Emu
Bay Railway south from Guildford came within 20 kilometres of the mine. This guaranteed it sporadic
attention from miners and may account for the stack of iron rails on the mine site which may post-date the
original work.
Comparative analysis
Most other 1890s Tasmanian hydraulic gold mines have few intact features and/or are difficult to access.
The Corinna Hydraulic has relatively intact water races (including one passing intact under the Corinna
Road) but little else in the way of infrastructure; the Brookside Hydraulic near Corinna has been obliterated
by the Corinna Silica Mine; the isolated Lucy Spur Gold Mine, located high above the middle reaches of the
Pieman River, has little infrastructure and is accessible only by helicopter. The Lucy Spur combined a
hydraulic sluicing operation with hard rock mining at a small adit, where an 1886 Huntingdon mill (a small
crushing device) remains. The mining face for the hydraulic operation contains an interesting feature, a dump
shaft by which mullock or overburden was removed from the mining face, but is being engulfed by bauera.
Fallen timber and regrowth resulting from a recent fire make movement across the site very difficult . Sluiced
mining faces but little other infrastructure are still observable at the sites of the Bell Mount Gold Mine
(inaccessible on private land near Moina) and the Beaconsfield and Salisbury Hydraulic Gold Mine
Wednesday, July 10, 2019 Page 3 of 6
(accessible on a forestry reserve near Beaconsfield). None of these sites has a level of integrity comparable
to that of the Mayday Hydraulic.
Hydraulic sluicing for tin is demonstrated at the Iris Tin Mine near Moina . The mine is located on an elevated
flat. Water was brought to it on a slight downhill grade from two dams, and conveyed around the site by
wooden pipes bound with wire. In the twentieth century a diesel engine was used to increase water
pressure. The mining faces, races, dams, wooden pipes, sluice boxes and hut sites are still visible. Norm
Clark’s hydraulic elevation operation for osmiridium near Adamsfield is also easy to interpret , with water
being conveyed by race to a dam and from there, as needed, conveyed to the mining face by metal pipes.
Two intact huts remain on site. Norm Clark used telescoping pipes and probably a diesel engine to increase
water pressure, but hydraulic elevation was a slightly different process to conventional hydraulic sluicing , in
that mineral-bearing dirt or rock was effectively sucked up into sluice boxes .
References
Advert, Cornwall Chronicle, 25 January 1878, p.1.
Advert, Mercury, 22 October 1895, p.4.
Advert, Mercury, 6 January 1896, p.4.
Austral Archaeology 2002, Van Diemen’s Land Company sites: Conservation Management Plan, report to
J&T Gunn, Austral Archaeology, Hobart.
Bell, WR 1895, ‘Report on trip of inspection to Middlesex and vicinity’, 13 May 1895, EBR13/1/2 ( Tasmanian
Archive and Heritage Office, afterwards TAHO).
Bell, WR 1896, ‘Report on the hydraulic gold workings at Lower Mayday Plain ...’, 14 May 1896, EBR13/1/2
(TAHO).
‘Black Bluff’, Tasmanian Democrat, 12 July 1895, p.3.
Blainey, Geoffrey 2003, The rush that never ended: a history of Australian mining, 5th ed., Melbourne
University Press, Carlton, Vic (first published 1963).
Correspondence, Van Diemen’s Land Minerals Company, 1882–92, VDM1/1/1 and VDM2/1/1 (TAHO).
‘Death of a Tasmanian geologist’, Evening Post, 27 June 1899, p.5.
‘From Paradise to Beulah’, Launceston Examiner, 1 March 1893, p.3.
‘Gold at Mayday’, Daily Telegraph, 12 September 1911, p.2.
Greever, William S 1963, The bonanza west: the story of the western mining rushes, 1848–1900 , University
of Oklahoma Press, Norman, Oklahoma.
‘House of Assembly’, Mercury, 9 August 1894, p.4.
‘Hydraulic sluicing in Tasmania’, Launceston Examiner, 12 December 1892, p.3.
‘Hydraulic sluicing in Tasmania’, Launceston Examiner, 10 February 1894, p.8.
Idriess, Ion L 1979, Prospecting for gold, other minerals and precious stones , Angus & Robertson, Sydney
(first published 1931).
‘Items of news’, Mount Alexander Mail, 21 October 1873, p.2.
‘A merry party’, Launceston Examiner, 29 February 1892, p.4.
‘Mining’, Mercury, 29 June 1895, p.1.
‘A mining deputation’, Mercury, 30 June 1893, p.3.
‘Mining news’, Tuapeka Times, 17 June 1891, p.3.
‘Mining notes’, Tuapeka Times, 11 January 1893, p.5.
Wednesday, July 10, 2019 Page 4 of 6
‘Mining notes’, Tuapeka Times, 27 June 1894, p.3.
Montgomery, Alexander 1894, Report on the Corinna Goldfield.
‘The Rise and Shine Co’s Claim, Pomahoka’, Otago Witness, 18 May 1892, p.3.
‘Sluicing the Bendigo Creek’, Bendigo Advertiser, 1 April 1893, p.4
‘Social gathering at Tuapeka West’, Tuapeka Times, 20 May 1891, p.3.
‘Sweet Marie’, Kalgoorlie Western Argus, 5 November 1896, p.10.
Thornily, EM 1897, ‘Some notes on hydraulicing and ground sluicing in New Zealand, and comparisons with
the drift gravel of the Corinna district in Tasmania’ , Transactions of the Australasian Institute of Mining
Engineers (ed. AS Kenyon), vol. IV, Melbourne, p.55.
Statement of
Significance:
(non-statutory
summary)
The Mayday Hydraulic Mine is of historic cultural heritage significance because it demonstrates the
history of mining in Tasmania, particularly the hydraulic gold mining craze of the 1890s when perhaps
the attractive price of gold during economic depression had left investors vulnerable to ‘get-rich- quick’
gold schemes; because it is a rare, largely intact example of a hydraulic gold mine in Tasmania ;
because it has the potential to contribute to an understanding of nineteenth- century Tasmanian gold
mining and the life experiences of gold miners; and because it represents a distinct class of about 30
hydraulic gold mines established during the craze of the 1890s.
The Heritage Council may enter a place in the Heritage Register if it meets one or more of the following criteria from the
Historic Cultural Heritage Act 1995:
Significance:
The Mayday Hydraulic Mine demonstrates the history of mining in Tasmania , in particular the hydraulic gold mining
craze of the 1890s in which terraces containing gold-bearing gravels were sluiced at high pressure. It was a time of
economic depression when the fixed price of gold attracted investors who were vulnerable to ‘get-rich- quick’ schemes.
Hydraulic sluicing for gold was untested in Tasmania but had been highly successful on the Otago goldfields of New
Zealand. It did not work in Tasmania because of the elevated level of many of the terraces , making it difficult to supply
them with high-pressure water, and because of the comparatively small amount of gravel available to sluice which
made the process uneconomical. Most companies exhausted or almost exhausted their funds on infrastructure before
discovering that their claims were unpayable. With its extensive water gathering system still in place but a
comparatively small amount of mining evident, the Mayday Hydraulic Mine clearly demonstrates this disastrous
overcapitalisation on an unproven proposition.
The place is important to the course or pattern of Tasmania’s history.a)
b)
The Mayday Hydraulic Mine is the most intact hydraulic gold mine in Tasmania , having at least two water races
mostly intact, all its telescoping pipes, metalwork, and some of its wooden fluming still in place, and the mining face
and mullock heap of the operation still evident. The story of how the mine operated is easily interpreted from these
features. While the operation of motor-driven hydraulic mining is evident at tin mines such as the Iris Mine near Moina
and at osmiridium workings at Clark’s Huts near Adamsfield, these differed markedly from the sluicing of the gold
mines which relied on gravity to raise water pressure. No other Tasmanian hydraulic gold mine has such intact
features as the Mayday Hydraulic. Nor do the others so clearly demonstrate how they operated or the failure of the
hydraulic gold craze of the 1890s.
The place possesses uncommon or rare aspects of Tasmania’s history.
c)
Apart from the intrusions of a road and power lines, the site of the Mayday Hydraulic Mine has remained largely
untouched since it operated. The well-preserved site has the potential to reveal information about
late-nineteenth-century mining technology and the living conditions of late-nineteenth and early-twentieth-century
miners. Several hut sites are apparent but little archaeological work has been conducted. The hut sites have the
potential to reveal information about the lives of nineteenth-century miners and the operation of nineteenth-century
hydraulic gold mining.
The place has the potential to yield information that will contribute to an understanding of Tasmania’s
history.
Wednesday, July 10, 2019 Page 5 of 6
d)
In the period 1893–1901, at a time of economic depression, hydraulic gold mining was a craze in Tasmania, investors
being attracted by the fixed price of gold and the promise of a mining technique which had been highly successful on
the Otago, New Zealand goldfields. About 30 mines of this kind were established. The Mayday Hydraulic Mine is the
best preserved of any of these mines, with its telescoping pipes, water races and even remains of its wooden flumes
still in place and its mining face and mullock dump clearly discernible. The features of the Mayday Hydraulic clearly
demonstrate the conveying of water to the site via races and flumes surveyed to a uniform grade, the collection of
water from races in a holding tank, the generation of high pressure by plunging that water steeply downhill through
telescoping pipes and the use of that high-pressure water to blast away a mining face, washing the gold-bearing rock
into sluice boxes, the waste rock being expelled into a tail race, that is, into a convenient tributary of the Mackintosh
River. The mining face, trial adit, trenches and mullock heap also help demonstrate the mining operation. The high
capital cost of establishing the infrastructure for such a mine is also clearly evident.
The place is important in demonstrating the principal characteristics of a class of place in Tasmania’s
history.
e)
The skill of surveyors and hydraulic engineers in maintaining the uniform grade needed to move water over distances
by gravity through hilly terrain without the aid of contour maps and digital technology is remarkable. While the
Mayday Hydraulic races are not particularly long, one of them embodies the challenge of bringing water across a
divide, that is from the head waters of the Leven River to the head waters of the Pieman River. Given the reliance on
gravity to move the water, a tortuous route had to be found around the high ground between these water systems in
order to maintain the necessary downward grade.
The place is important in demonstrating a high degree of creative or technical achievement.
f)
No Data Recorded
The place has a strong or special association with a particular community or cultural group for social or
spiritual reasons.
g) The place has a special association with the life or works of a person, or group of persons, of importance in
Tasmania’s history.
No Data Recorded
h) The place is important in exhibiting particular aesthetic characteristics.
No Data Recorded
PLEASE NOTE This data sheet is intended to provide sufficient information and justification for listing the place on the
Heritage Register. Under the legislation, only one of the criteria needs to be met. The data sheet is not
intended to be a comprehensive inventory of the heritage values of the place, there may be other heritage
values of interest to the Heritage Council not currently acknowledged.
Wednesday, July 10, 2019 Page 6 of 6
CPRDRAFTDate Registered:PREPARED BY
HERITAGE TASMANIA
No. PRODUCTION / AMENDMENT AUTHORITY REFERENCE DRAWN APPROVED DATETASMAP: GRID: DATUM: CONTOUR INTERVAL:
0 10.5km
1:15,000SCALE
Mayday Hydraulic Mine
Lot 1
LEA - 4040, PENCIL PINE 4039 MGA94 / ZONE 55 AHD N/A
1 Production THC 10674 AW
Locality Plan
Note1. Lots 1, 2 & 3 represents the registered boundary for 'Mayday Hydraulic Mine', #10674 on theTasmanian Heritage Register.2. Lot 1 is the partial parcel of FR 144941/1 & PID 3393161, the boundary of which is marked by a heavy black line and described below.3. Lot 2 is the partial parcel of FR 144941/1, the boundary of which is marked by a heavy black line and described below.4. Lot 3 is the partial parcel of FR 144941/1, the boundary of which is marked by a heavy black line and described below.5. All boundaries are parcel boundaries, details of individual land parcel boundaries may be accessed through the Land Information System Tasmania (LIST).
DRAFT
p.p. Surveyor General:
CENTRAL PLAN REGISTER
XX-XXX-17
PID 3393161
±DRAFT
Guildford Road, Guildford
~3.957 ha
LPI GGK84
FR 144941/1
Point & Boundary Description - Lot 1A. Intersect of 750m contour & road parcel at 403940EA-B. Northern edge of road parcel. B. Meeting point of road parcel & FR 144941/1 & PID 3393161B-C. Line running parallel & offset from road centre line by 20mC. 404572E, 5401195NC-D. Straight lineD. 790m contour line at 5401226ND-E. 780m contour lineE. 790m contour line at 404500EE-F. Straight lineF. 750m contour line at 5401251NF-A. 750m contour line
FR 144941/1
FR 144941/1
LPI GGB23
FR 144941/1 (Belvoir Road)
power lines
PID 3393161
Belvo
ir Road
Lot 2~1.812 ha
Lot 3~41.74 ha
Lot 2G. Intersect of 760m contour & road parcel at 403985EG-H. Southern edge of road parcelH. Intersect of 750m contour & road parcel at 403745EH-I. 750m contourI. 750m contour line at 403691E, 5400690NI-J. Straight line running parallel to power line offset 20m to the northJ. 760m contour at 403987E, 5400775NJ-G. 760m contour
A
BCDEF
GH
IJ
K
L
M
N O
Lot 3K. 750m contour line at 403679E, 5400638NK-L. 750m contour L. 750m contour line at 403434E, 5399708NL-M. Straight lineM. 402954E, 5399590NM-N. Straight lineN. 402950E, 5399263NN-O. Parcel boundary O. Intersect of parcel boundary & 890m contour at 403888E, 5399278NO-P. Straight lineP. 760m contour line at 5399802NP-Q. 760m contour Q. 760m contour at 403981E, 5400735NQ-K. Straight line running parallel to power line offset 20m to the south
P
Q