A brief history of the historic and unusual construction of Lismore Bridge

An ancient road existed before the 12th century linking Cashel, Ardfinnan, Lismore and Ardmore, called the Rian Bo Phadraigh or track of St. Patrick's cow. It crossed the Blackwater at Lismore, probably by a ford.

Joyce states that St.Carthac, the founder who died in 638, named it Liassmor or the great enclosure. It became a great centre of learning. The first castle is attributed to Prince John, the Norman Lord of Ireland in 1185, who became the “bridge building monarch” in 1199. No reference to an early bridge at Lismore was found; perhaps there are mentions in the famous Book of Lismore compiled in the 15th century, as it is said to contain much secular information in addition to the lives of Irish saints.
The Down survey maps show a ford about five miles up river and a bridge at Cappoquin in the 1650s. Moll’s map shows bridges at Ballyduff and Cappoquinn, but no crossing in the vicinity of Lismore. The importance of the town diminished after it was burned in 1645. It revived when the fifth Duke of Devonshire inherited the castle and large estates in 1753. Ryland’s History of Waterford (1824) states that he spent large sums erecting a sessions house and a gaol, an inn and offices and more importantly the bridge. Ryland includes a sketch of the bridge by Brooks and states that “it was built at the sole expense of the late Duke in 1775 and is 100ft in span of the arch.” Various secondary sources give a range of cost, up to 9,000stg and state that the bridge was designed by Thomas Ivory, the noted 18th century Irish architect.

McParland’s 1973 booklet ‘Thomas Ivory, Architect’ gives the source as ‘Council Minute Book, 1770-1801; Waterford Town Hall; July 13, 1773. Austin Cooper noted on June 11, 1781 (Nat Library of Ireland Ms 772) that according to the Duke of Devonshire’s agent, the Lismore bridge ‘designed by Mr Ivory and executed by Messrs Darley and Stokes’ had cost 7,200stg”. This is an invaluable mention and from it we can deduce that the six span bridge shown in the sketch was the original designed by Thomas Ivory and erected in the 1770s.

There is another sketch of the bridge, drawn by John Brennan and printed in the Irish Penny Magazine in 1833. The sketch shows five arches, the sixth small arch being obscured by trees. The overall profiles, drawn from locations well back from the right back looking up river, are quite similar.
The main arch and the first have a deceptive pointed appearance at the crowns due to the oblique angle from which they were viewed. The article in the magazine on Lismore has one sentence about the bridge. “Here is a fine bridge, over the Blackwater, erected at very great expense by a former Duke of Devonshire and particularly remarkable for the extent of its principal arch, which spans ninety feet.” One important deduction that can be made from Ryland and the latter article is that there must have been no plaque on the bridge; otherwise one would expect specific information from it to be quoted, including a mention of Thomas Ivory.

There seems to have been no public road here before the erection of the bridge, otherwise the Waterford grand jury would have received some mention. New roads were being built all over the country at the time in accordance with the provisions of the 1774 act, but it would be difficult to envisage any grand jury spending over 7,000stg on a new crossing on the estate of a wealthy, often absentee landlord. The insertion of the note in the council minutes book tends to confirm this opinion.
The 1842 OS six inch map shows the river to be about 220ft wide between the banks at the bridge. A substantial pier with cutwaters fore and aft is shown in the river, such that the main south arch had a clear span of about 100ft, the second scales about 70ft. The land arches are not distinguished, indicated by a lack of cutwaters.

I had looked at this bridge briefly in 1986, before searching out the foregoing information and noted down the inscription of the present plaque: “1858/Lismore Bridge/Rebuilt/CH Hunt and EP McGee Contractors/Charles Tarrant Engineer CS”. It gives the impression that the whole bridge had been rebuilt, though the plaque is not located on the main span, but on the third pier on the down river parapet. A close examination of an old Lawrence postcard in which the main arch is depicted clearly without foreground camouflage, showed that the main arch spanning the river had not been rebuilt and was obviously Thomas Ivory’s original. A difference was noticeable, particularly in the apparel on the arch ring extra-dos. This was confirmed by the county engineer, John O’Flynn, who also drew attention to a distinct change in the masonry in the parapet walls.

Information on what had happened to Thomas Ivory’s land arches emerged fortuitously in a search for information on Carrigadrohid Bridge. Among the reports in the Cork Examiner of November 11, 1853 on the damage caused to bridges in Co Cork by the big flood of November 3 was a mention of Lismore. It stated that some dry arches had been destroyed and that a ferry had been established just below the bridge and that the County Surveyor was making arrangements for the erection of a temporary wooden bridge which would not interfere with the rebuilding of the arches which were destroyed. The report also mentioned that the wooden bridge at Ballyduff, four miles up river from Lismore, was completely carried away by the flood.

There is an entry in the records of the Co Waterford spring assizes, 1854 providing “To the County Surveyor, amount of magistrates’ warrant for repairs of a sudden damage to the bridge of Lismore 20stg and another in the summer assizes 1854 “To Albert Williams, of Dublin for repairing the bridge of Lismore, on the road from Waterford to Cork, pursuant to the plan and specification of the county surveyor and that the treasurer do, out of any funds in his hands available for the purpose, make advances to the contractor during the progress of the work, on the certificate of the county surveyor, in sums not less than 250stg and in the whole not exceeding 1,000stg (provision) 2,000stg.” These items obviously relate to the temporary wooden bridge at the fallen land arches because the plaque states that Hunt and McGee were contractors for the §858 rebuilding.

Robert Manning, in his presidential address to the ICEI in 1879, stated that Lismore Bridge “is a stone bridge with a (centre) arch of 103ft span and a rise of 23ft. It is the largest span in Ireland except that over the Liffey at Islandbridge, which has a span of 104ft and a rise of 30ft. Manning had carried out a survey of Lismore, north of the river Blackwater in 1870. The Waterford Co Council ‘Report on Bridge’ 1918 records that Lismore bridge was 24ft 4in wide overall, had seven arches with spans and piers as follows: 101’/33’-6”/47’-3”/9’7”/44’-3”/6’-9”/44’-3”/6’-9”/44’-3”/6’-8”/43’9”/6’-8”/40’-9”.

On its general condition, it stated it was good apart from partial undercutting of some floors under the land arches in high floods which was repaired for 65stg.

The main span of Lismore, that is, the surviving arch of Thomas Ivory’s bridge was measured and examined by Pat Corbett, Assistant Engineer, Waterford Co Council in 1990 using electronic distance measurement. He found the span to be 100ft from abutment to the face of pier 1 at the springing points. He also measured and plotted the intrados curve and found that the springing on pier 1 was 7ft 9in below the level of the abutment springing. This remarkable characteristic is not visible to the eye or old or new photographs due to obstruction by trees and shrubs. This was how Ivory avoided minimising the visual effect of the change of grade in the parapet coping over pier 1, slightly evident in the Brooke sketch. The rise of the arch is 29ft, giving a rise to span ratio of 0.29. The riverbed is 10.5ft below the span line and almost parallel to it.

The abutment is founded on rock and most probably pier 1. The intrados curve has not been fully investigated, but from the measurements it would appear to be a segment of a circle of 57ft 9in radius with an internal angle of 120 degrees. The ring is composed of voussoirs approximately 46in deep at the crown and 30in by 18in wide on the soffit.

There is a significant difference in the stone masonry in the main 1775 arch and the 1858 land arches, clearly evident in the parapet and spandrel walls. There is no significant difference in the masonry in pier 1, which is 34ft wide and obviously designed by Ivory as an abutment pier; this, together with the lowering of the main arch springing plane, saved the 100ft arch from sequential collapse in the 1853 flood. It is a landmark arch in the history of Irish masonry bridges and a monument to a courageous architect, a master of stonework who was born in Cork in the 1730s. His interest in long spans was probably stimulated by the 60ft span of Clarke’s Bridge erected across the Lee by Hobbs in 1766.

courtesy of The Avondhu