Thanks for the comments Geoff, I've a love of bushwalking and bushwalking history, and it's always interesting to hear different perspectives on the same subjects!
I'll have to go off and do some more research on the Lost Rock matter, however, I acquired a book last week and upon flicking through it found some relevant information regarding the Nellies / Nellys debate.
From Katoomba to Jenolan Caves: The Six Foot Track 1884-1984 / Jim Smith 1984 (Page 77)
Nellie’s or Nelly’s?
According to Billy Lynch (‘E.D.H.’ 1896) the Aboriginal name for Nellie’s was ‘Kooranbarook.’ Europeans have been divided by between ‘Nellie’s’ and ‘Nelly’s.’ Both are used in old and recent maps and guidebooks, with or without a variably placed apostrophe. An early variant is ‘Nella’s Glen.’
We are not assisted in this dilemma by the disagreement of two authorities. Quilty 1948 states: ‘[J.B.] North was interested also in the Megalong side, and the Glen came to be known as ‘Nellie’s Glen’ named after his wife, Mrs. Nellie North.’ but Bennett 1971 says: ‘North named ‘Nelly’s Glen’ after his daughter Nellie.’ Genealogical research may establish whether Nellie was North’s wife or daughter.
Not all travellers were pleased with North’s immortalisation of his wife or daughter. ‘Locksley’ 1887 referred to ‘the picturesque fissure known by the rather simpering name of Nellie’s Glen.’ While Jose 1888 described the ‘huge cleft (known most unreasonably as Nellie’s Glen)...’ Perhaps these early writers [thought] that the feminine and domesticated ring of the name was inappropriate for such wild scenery.
North intended the name to refer to the whole reach of the valley between Radiata Plateau and Narrow Neck where his mining activities were situated. Popular usage centred the name of the narrow pass in the cliffs utilised by the bridle trail and known in the earliest days as ‘Megalong Cleft’ (sometimes as Megalong ‘Cliff’, ‘Clift’ or ‘Pass’). This sliding of place names is an interesting phenomenon that I will explore in a later book on Blue Mountains place names.
The waterfall at the base of the Glen was originally known as the ‘Ethal Falls’ and sometimes as (yet another) ‘Bride’s’ or ‘Bridal Veil.’ Later these names were lost and the whole series of falls, of which the Ethal Fall is the last, became known as the ‘Bonnie Doon Falls.’
Appendix 8 of the book regarding 'The Black's Ladder Mystery' opens with the following paragraph:
Note: The term 'Megalong Cleft' is used here for the break in the cliffs known today as Nellie's Glen, and the term 'Nellie's Glen' for the reach of the Megalong Valley between Radiata Plateau and Narrow Neck.
Further, in Smith's 'How to See the Blue Mountains, 2nd Ed.' (1986), a section on 'Nelly's Glen: Radiata Plateau and Narrow Neck' included the following comments:
The routes into the arm of the Megalong Valley between Radiata Plateau and Narrow Neck are: the Water Board ladders, the Devil's Hole, and Nelly's Glen. Rockclimbers have made a track at the base of the Narrow Neck cliffs from the bottom of the ladders. Nelly's Glen is the start of the 100 year old 'Six Foot Track,' a bridle trail between Katoomba and Jenolan Caves. Nelly's Glen refers more correctly to the whole reach of the Megalong Valley between Elphinstone (Radiata) Plateau and Narrow Neck, The break in the cliffs forming the start of the Six Foot Track is known as the Megalong Cleft.
Smith's maps reflect this description, with 'Nelly's Glen' placed in the valley between Radiata Plateau and Narrow Neck, and 'Megalong Cleft' where the currently GNB approved 'Nellies Glen' lies.
Jim Barrett, in his 'Place Names of the Blue Mountains and Burragorang Valley' (1994) book provides the following entry and footnote:
Nellies Glen
Entry - Believed to be named after Nellie North, wife of the mining entrepreneur J.B. North, but it has also been attributed to North's daughter. The Aborigines' name for the glen was Kooranbarook.
Footnote - At the bottom of Nellie's Glen at the turn of the 19th century was the site of a village which served the Megalong miners, then known as Dunbar's Flat. The bush walkers of post World War II always affectionately referred to this spot as 'the pub site', because the centre of the thriving little community was Long's Hotel.
So what does all this mean?
SpellingWell, it seems that both variants of the spelling have been used throughout the years (and given the same pronunciation you can see how this could come about). Nellies is the currently GNB approved version, and if Smith and Barrett are both right in that North's wife was named Nellie, then you would think this version should prevail inline with GNB naming policy (spelling of names should be consistent which what/who they are named after). Some further research into 'Nellie North' would be useful here.
The spelling used on Ford's map seems consistant with the usage of the time.
LocationThis I think is a little more interesting and requires further research. Smith is quite clear on where the historic usage was applied (in the valley) however it would be useful to have some more understanding as to how he came about this interpretation. I would think an inspection of the historical accounts of the Six Foot Track (which Smith covers in another publication of his I have but are yet to read) would reveal where the name was applied.
If it is the case that historically the name applied to the valley, then the currently application of the GNB naming to Smiths 'Megalong Cleft' is incorrect.