Thursday 21 May 2020

Mapping Mountains – Hill Reclassifications – The 500-Metre Tops of England and Wales – Deweys


THIS HILL HAS SUBSEQUENTLY BEEN DELETED FROM THE DEWEY LIST


Linghaw (SD 637 985) – Dewey addition

This is one in a series of retrospective Hill Reclassification posts that detail hills whose status has altered in the listing of the Deweys and where I have had direct association with the status change.  These posts will tie in with a forthcoming Change Register giving detail to this list and its alterations since publication in the Mountain tables book.

At the summit of Linghaw during the Leica 530 survey that subsequently deleted this hill from the list of Deweys

The 500-Metre Tops of England and Wales are affectionately known after their hill list compiler; Michael Dewey.  This list mixes metric and imperial height in its criteria to bookend up to the 2000ft height band and takes in all hills in England, Isle of Man and Wales that are 500m and above and below 2000ft (609.6m) in height that have 30m minimum drop.

This list formed one of a number of lists that appeared in the Mountain tables book published by Constable in 1995 and at the time of publication comprised 373 hills with 164 in England, 5 in the Isle of Man and 204 in Wales.  The Deweys have undergone extensive revision since first publication with the initial stages forming the basis of this revision given below:


1995    Mountain tables published by Constable with 373 hills listed as Deweys.

April 2000    Strider (LDWA quarterly booklet) publishes contact details for David Purchase and Myrddyn Phillips who have found and list 24 and 14 possible new 500m tops respectively.

It was expanded versions of the above two lists that formed the basis of the next publication:

25th May 2000    List of Possible 500 Metre Tops by Michael Dewey listing 44 hills.

David Purchase expands his Additional Dewey 500m Hills and Myrddyn Phillips produces lists of English 500m hills to measure and Welsh 500m hills to measure.

These lists formed the basis of the next publication:

29th June 2000    Possible/Probable 500’s by Michael Dewey listing 77 hills.  Michael adopts following protocol; if one person proposes that a top should qualify as a 500 by personal survey, and is then confirmed by a second person, it should then be promoted to the main list.

April 2002    The 500+ Tops of England and Wales – The ‘New Deweys’ published in the Strider booklet and listing 66 new qualifying hills.

25th May 2006    Rob Woodall republishes Michael’s main and possible/probable lists on the RHB Yahoo group file database. 

Mountain tables by Michael Dewey


The details for this addition appear below:

The name the hill is listed by in the Deweys is Linghaw, and it is adjoined to the Howgill Fells in the Great Shunner group of hills which are situated in the Yorkshire Dales in England, and it is positioned with the A685 road to its north, the M6 motorway to its west, and the A683 road to its east, and has the town of Sedbergh towards the south south-east.

This hill was not included in the original 1995 Constable publication, but with a small uppermost 500m ring contour and col contouring between 460m – 470m that appear on the Ordnance Survey 1:25,000 Explorer map, this hill has a minimum of 30m of drop according to contemporary Ordnance Survey maps and therefore was an automatic entry to the listing of Deweys. 

Extract from the Ordnance Survey 1:25,000 Explorer map

The above detail was noted by David Purchase and Myrddyn Phillips who worked independently but also exchanged all data.  These details were forwarded to the list author; Michael Dewey and the hill was added to the list on the 3rd May 2000.

As the summit height is the minimum required for qualification to Dewey status this hill was prioritised for a GNSS survey and this took place on the 20th October 2010.  The summit and col of this hill were surveyed by John Barnard, Graham Jackson and Myrddyn Phillips using a Leica 530 with 60 minutes of data gathered at the summit and 30 minutes at the col.  The survey resulted in a 498.9m summit height and a 463.45m col height, with these values giving this hill 35.4m of drop.  As the summit height is below 500m this hill was subsequently deleted from the list of Deweys (see later Hill Reclassifications post).

  
The full details for the hill are:

Name:  Linghaw

OS 1:50,000 map:  97

OS 1:25,000 map:  19

Summit Height:  c 500m (interpolation)

Summit Grid Reference:  SD 63764 98540 (interpolation)

Col Height:  c 465m (interpolation)

Col Grid Reference:  SD 63976 98485 (interpolation)

Drop:  c 35m (interpolation)


Myrddyn Phillips (May 2020)





No comments: