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The marvel of Moista Sound

Townland tales

Erris: Belderg to Porturlin via Laghtmurragha


John O'Callaghan

By the time the acclaimed travel writer, Eric Newby, wrote ‘Around Ireland in Low Gear’ (1987), he had already published over 20 travel books, in a career stretching from 1956 to 1999.
In 1969, he co-authored ‘Wonders of Ireland, A personal choice of 484’, with Diana Petry. Of the 35 ‘wonders’ listed for County Mayo, one that intrigued me most was ‘Moista Sound’. Of all the anglicised, mispronounced and probably mistranslated corruptions of a placename, this one sticks out a mile.

Churning up old meaning
Until 2015, the closest place to Moista Sound on the OS maps – including the first four editions of the 1:50,000 ‘Discovery Series’, sheet 23 – was a tiny island named ‘Illanmaster’, located roughly mid-way between Belderg and Porturlin.
Six years ago, on publication of the fifth edition, the name of the island changed to Oileán Máistir. This has been translated to ‘Máistir’s Island’ on Logainmneacha.ie, and this is what John O’Donovan accepted in 1838, ‘island of the master’.
In 2014, Fiachra Mac Gabhann added that ‘two saints named Master are listed in the Great Genealogy, and two laity called The Master’. He was referring to ‘Leabhar Mór na nGenealach’, ‘The Great Book of Irish Genealogies’, compiled (1645-66) by Dubhaltach Mac Fhirbhisigh, ed. Nollaig Ó Muraíle (Dublin 2003).
However, all the local people, including the fishermen, pronounce the name of the island as ‘My-ster’, not ‘Maw-ster’. Therefore, an Englishman or Anglo-Irishman, such as Newby or Thomas Johnson Westropp, or the 19th-century geologists who studied the cliffs here before the OS arrived, may be forgiven for writing ‘Moista’ for ‘My-sta’.
I would go further and propose that, rather than being a corruption of ‘Máistir’, the name comes from the Irish word ‘maistreadh’ meaning ‘churning’, as in ‘maistreadh na mara, na dtonn’, the churning of the sea, of the waves (cf. Foclóir Gaeilge-Béarla, Ó Dónaill, 1977, p. 822).   

Trap-dykes and sea arches
My own effort to visit this ‘wonder’ led to one of the most memorable, spectacular and challenging transverse walks I have ever undertaken, from Belderg to Porturlin, westwards along the north Mayo coastal cliff-tops.
This is not a walk for the faint-hearted or anyone who experiences vertigo; it should not be attempted lightly or on a whim, as the cliffs are high, exposed, and, in some places, unstable and liable to landslide. However, with all due caution and care, the natural wonders that are revealed en route are a delight to behold and well worth the slog involved in getting to see them. The walk traverses four townlands: Belderg (in Tirawley), and Laghtmurragha, Srahataggle, and Porturlin, all in the Barony of Erris.
Aside from the etymological interest that the name provokes, the most unusual topographical features encountered along the way are what geologists once referred to as ‘trap-dykes’ or what in Scotland is called a ‘geo’ or chasm.
Trap-dyke is the technical term for the 200-metre-long and 2- to 3-metre-wide channel that falls between Illanmaster/Oileán Máistir and the mainland, where the cliffs rise to 238 m above sea level. Generally speaking, it is defined as a sheet-like body of igneous rock cross-cutting other rock types, and north Mayo is a rich area for these dykes.
The dramatic visual impact of the narrow rift or channel between the island and the mainland is an extraordinary sight when seen for the first time, approaching from the western slopes of Glinsk. I could not but be impressed to witness this truly natural ‘wonder’.
Cesar Otway, who first described his visit to this area by boat in 1841, waxed lyrically about the ‘sublime’ nature of the ‘clean-cut’, almost like a ‘saw-cut’ nature of the narrow channel, so narrow that they had to pull in their oars for the 200m passage through.
He observes an eagle taking flight ‘on the brow of Islan Maistre’ (sic; note the phonetics, ‘my-stre’, not ‘má-stir’) and urges his boatmen to ‘Rest on your oars a little, boys; why so fast? the day is long. I can never expect to see this again—give me the means of such enjoyment a little longer’. One of his companions on the day was a local rector from Killala, Joseph Verschoyle, who drew the ‘Moista Sound’ for Otway’s book.
Five kilometres westward, closer to Porturlin, we observed the result of another trap-dyke, a 5-metre-high arch in a 90-metre cliff, that proved quite difficult to photograph from the land side, without a lengthy detour. Apparently, you can row a boat through it also, at low tide. Imagine.

John O’Callaghan MA MBA PhD is a mountain walk leader and has organised and led expeditions both at home and abroad. He has served on the board of Mountaineering Ireland and is currently on the Irish Uplands Forum board. In 2012, he wrote the winning article that secured Westport’s accolade as the Irish Times’ ‘Best Place to Live in Ireland’.