The Corbetts guidebook lists the number of qualifying hills as 219 but for a long time they were counted as being 220 - Dave Hewitt looks at the Corbetts contradiction.
The doorbell rings and the postie brings a parcel - the revised edition of the SMC's Corbetts guidebook. A pleasant surprise - the club had asked me to write a couple of hundred words about the Ochils (included among the "other Scottish hills" of the title), but I hadn't really expected to be sent a copy of the finished product.
And a nice-looking product it is - I've not as yet had chance to read right through (and anyway, being a guidebook, it's really a dipper-inner), but the photographs are great and the overall production quality is high (although someone seems to have forgotten to proof-read the picture captions, home to several clumsy typos, eg "Shiehallion"). There is no doubt that it will sell well over the Christmas period and beyond. Co-editors Rob Milne and Hamish Brown and their team of contributors appear to have done a good job.
My admittedly small vested interest as one of those contributors (plus the inclusion, on the book's maps, of the Corbett Tops - a list which I had been involved in publishing in 1999) means that I can't in all honesty review the thing. But in this and the next column I do want to pass a couple of extended comments on aspects with which I haven't been involved.
The first is that The Corbetts and Other Scottish Hills states boldly on its back cover, and on page six in its introduction, that there are 219 Corbetts. Hoo-blooming-ray. To adapt a catchphrase of a well known but currently absent TV quiz-show host, "That is the right answer."
The SMC has been publishing the list of Corbetts - Scottish hills of between 2500ft and 2999ft (762m-914m) with 500ft of drop, although the Englishman Corbett would have been shocked to see the English and Welsh equivalents excluded - for 50 years now and this is the first time that the correct figure for the number of qualifying hills has been given. Indeed the problem relating to the overall number of Corbetts hadn't even been properly addressed since 1953.
The trouble centres on any pair of hills where the mapped height is the same for both but where the drop between is less than the requisite 500ft. Curiously, the list has always included one such problematic pair at any given time, although three such pairings have featured over the half-century-odds since John Rooke Corbett died on 13 August 1949.
Corbett's data first hit the printed page in April 1952, in issue 143 of the SMC Journal, and the list quickly reached a wider public when a revised edition of Munro's Tables appeared the following year. The first pair of "twin" Corbetts was Carn na Laraiche Maoile and Carn na Saobhaidhe in the Monadhliath. From 1952 to 1981 these were both credited with 2658ft in the imperial-heights version of the list and then 810m in the metric version, but they clearly didn't both qualify as Corbetts in terms of the original (and still current) definition.
This was known at the time, as Edmund Hodge, quoted by the list's initial editor John Dow in the 1953 SMC Journal, commented that, "two hills of equal height [...] which are 2 1/4 miles apart, and divided only by about 350 feet of dip [...] are probably included as alternatives, or joint claimants". Exactly right. Had that clear-sightedness been transferred to the published list then a long-running confusion could have been averted at a very early stage. The absence of Corbett Tops however led to an unindented layout when the tables were published, and so the Monadhliath pair appeared on the page as two distinct Corbetts. They weren't, and none of Corbett, Dow or Hodge would have viewed things this way. But as the years passed, no one really seemed bothered (or, perhaps, fully understood) that the list included one more hill than should strictly have been there.
Then, in 1981, the Monadhliath situation was resolved by the back door when a remapping of Carn na Saobhaidhe suggested that it was higher than its neighbour. (This continues to be the case: Carn na Saobhaidhe is currently mapped as 811m, against 810m for Carn na Laraiche Maoile.) That should have been problem sorted, end of story - but Sod's Law kicked in and the same set of Ordnance Survey revisions suggested that the previously undisputed Corbett Gairbeinn was now the same height as its neighbour Corrieyairack Hill. Both were mapped as 896m, but again the dip fell short of that required, at around 137m. Into the published list they both went nonetheless - even though any Corbettbagger traversing them on the ground would have known, if only by the unaccustomed ease of legwork, that something was wrong.
This revised version of the confusion lasted for 16 years, until a further remapping of Corrieyairack Hill saw it reduced to 892m in the 1997 Munro's Tables revision. Again, that should have been that, but again a new pair of conjoined summits appeared, this time much further west - Buidhe Bheinn and Sgurr a'Bhac Chaolais, the highest bumps on a contorted ridge between Glen Shiel and Loch Hourn. From 1952-81 Buidhe Bheinn had been listed as the Corbett (ie as the highest bump), and from 1981-97 it was demoted in favour of Sgurr a'Bhac Chaolais. Both of these decisions comprised normal procedure and were perfectly in order. In the late 1990s however it became clear (largely due to work by amateur map researcher Charles Everett) that the spot height for Buidhe Bheinn wasn't on the true summit and so both this hill and Sgurr a'Bhac Chaolais were eventually shown to be 885m above sea level.
(Don't trust the Ordnance Survey Explorer 414 on this, by the way - as with so many of the "new" Explorer maps it recycles redundant data plus - in a laughably poor piece of work - it awards Buidhe Bheinn a spot height of 897m. This sits inside an 870m contour and is a brutal misprint. The actual high point, elsewhere on the hill and located correctly inside an 880m contour, lacks any spot height at all even though the OS is known to have worked on providing an answer to Everett's query as far back as 7 February 1996, when they wrote to him saying: "...metric contouring for Buidhe Bheinn is available. The 879 metres spot height on the western spur is now 880 metres and a new spot height of 885 metres has been placed inside the 884 metres contour." Not for the first time in recent years the OS appears to be an organisation where staff in one department don't have a clue about work done by their colleagues down the corridor.)
Anyway, the new SMC Corbetts book does get the situation right, saying on page 177, "These two hills have been given the same height by the Ordnance Survey. As the drop between them is only 122m, they cannot both be Corbetts so have to be regarded as Siamese twins or part of a double summited Corbett and are given a unique joint status as one Corbett. Both summits should be visited by a prudent hillwalker to claim the Corbett..." Put another way, one of them is higher, even if at the molecular never mind cartographic level, but in terms of the current extent of our knowledge we just don't know which one it is, or at least we can't be sure.
Quite why the various versions of this error were maintained for half a century is open to speculation. My feeling is that it's largely due to the various editors of the tables having looked at things from a primarily Munrocentric standpoint. The initial editor, Dow, was the fifth Munroist, and even the apparently more clear-minded Hodge was a Munro man (listed as having completed in 1947). Similarly, subsequent editors - Jim Donaldson, Hamish Brown and the current incumbent Derek Bearhop - are also to be found among the Munroists. This, along with the inevitable higher profile of the Munros list - effectively the "meat" in any edition of Munro's Tables for the majority of hillgoers - has led to the "lesser heights" listings being treated as lesser lights, such that various errors and vaguenesses have slipped in (and stayed).
Munro's list is unusual in the hill world in that it has only one formal entrance criterion - height, or "absolute height" to use the jargon. A Munro or Munro Top has to be 3000ft or more to get in (never mind for now the absurd situation whereby the sub-3000ft Knight's Peak is currently included as a Munro Top - more on that another time), and while factors such as drop and distance from adjoining hills are certainly assessed in the equation, there has never been any formal definition.
Hence, in large part, all the debate and discussion and discontent every time changes are made to the list of Munros. The debatable changes are almost always "subjective" drop/distance-related ones rather than "objective" height-related alterations such as the demotion of Beinn an Lochain for being too low, or the promotion of Beinn Teallach when it was found to be high enough. Conversely, Corbett's list - like almost all hill lists - has two qualification criteria: height and drop, absolute and relative if you like. And these two criteria are of equal weight, so that if the drop between two candidate hills isn't deep enough then they should no more count as two separate Corbetts than if one of them was plainly below the crucial 762m/2500ft threshold.
In practical terms, twin summits such as Buidhe Bheinn and Sgurr a'Bhac Chaolais ought to provide no quandary for the aspiring Corbetteer - both should be visited before the full tick is counted - and, anyway, isn't a little extra legwork to be applauded rather than heckled? (At the time of the 1997 Munros revision a well-known hill commentator wrote a column in one of the glossy magazines in which he moaned about having to go back out and climb a few hills that he had missed - and missed quite deliberately - during his main Munrobagging career. My reaction on reading this was Eh? Isn't getting out on the hill what it's all about and isn't any hill list ultimately just a device to encourage enthusiastic activity? If someone prefers to sit around rather than climbing any given hill then no one is forcing them.)
A couple of final points on this. The whole palaver could have been avoided long ago had someone spent a minute or two looking properly at the most enduring twin-Corbett situation of them all - Creag an Dail Bheag and Carn Liath. These are two summits north of Braemar, each mapped as 862m and around a kilometre apart but with a mutual separation of just 34m. No one has ever seriously argued that these should be seen as distinct Corbetts - the walk between them takes ten minutes - and the Corbetts section of Munro's Tables has even from time to time acknowledged the awkwardness.
The 1981 edition, for example, included Creag an Dail Bheag in the main body of the list but added in a footnote that "Carn Liath [...] is also 862m and is more prominent from Braemar." The current edition lists just Carn Liath, with no mention of Creag an Dail Bheag and no footnote but this new Corbetts guidebook (page 121) notes that "Carn Liath has some half dozen tops of similar altitude on a bumpy summit ridge shaped like a wide H. The two highest are both shown as 862m and lie 1km apart but only count as one Corbett." That's fine and further good evidence that the new book's editors have finally displayed an understanding of what is, ultimately, just a typical list-related problem. Quite why such a simple, clearly stated method couldn't have been applied years ago to the other pairings is a mystery.
Which brings us on to the last point. The SMC is now something of a house divided. Go to a bookshop and the edition of Munro's Tables on the shelf will argue (wrongly) for 220 Corbetts. Alongside it the Milne/Brown guidebook will argue (rightly) for 219. This isn't really a problem as yet, but it will be interesting to see what happens next time there is some kind of revised edition of Munro's Tables.
A major revision is still a long way off but the SMC has tended to produce partial revisions every few years and the next of these cannot now be that far away (especially if existing stocks of the book are starting to run down). The Tables editor Derek Bearhop was lobbied about the 220/219 problem in the run-up to the 1997 publication of his book but proved resistant to any alteration. Given that things have now moved on, it will be interesting to see what happens next. Should Bearhop dig in and continue to argue for 220 then there could be some amusement ahead. A house divided tends, after all, to be a house worth watching.
Dave Hewitt
28/11/2002
The Corbetts and other Scottish hills is published by the Scottish Mountaineering Club, ISBN 0 907521 71 1, £18
You can contact Dave at Dave.Hewitt@dial.pipex.com
