In June 1732 the indefatigable Mary Delany (then still Mrs Pendarves following the death eight years earlier of her first husband) was staying in Killala, County Mayo with her friends Robert and Katherine Clayton: at the time he was Bishop of Killala. Writing to her sister Mrs Granville, she remarked, ‘About half-a-mile from hence there is a very pretty green hill, one side of it covered with nut wood; on the summit of the hill is a natural grotto, with seats in it that will hold four people. We go every morning at seven o’clock to that place to adorn it with shells – the Bishop has a large collection of very fine ones; Phill [Mrs Clayton’s sister Anne Donnellan] and I are the engineers, the men fetch and carry for us what we want, and think themselves highly honoured.’ It was the onset of a lifelong interest in shellwork that continued after she married Dr Delany in 1743 and moved to Delville on the outskirts of Dublin. Here Mrs Delany decorated various items, including urns and chandeliers, with shells and then in 1750 she turned her attention to the chapel attached to her husband’s house, eventually covering its ceiling with shell ornamentation. In December 1750 she wrote that during the evening, while another great friend Letitia Bushe read aloud, ‘I go on making shell flowers for the ceiling of the chapel. I have made 86 large flowers and about 30 small ones.’ The following month, ‘I am going on making shell flowers, six of the festoons are finished and fastened on; I have ten more to do, and a wreath to go around the window over the communion table.’ Later that summer a little grotto in the garden of Delville received the same treatment. In this activity, Mrs Delany was reflecting the fashion of her age.

Inspired by examples from ancient Greece and Rome, the origin of the modern era Shell House can be found in the grottoes that were a feature of 16th century Mannerist gardens in Italy. The Buontalenti Grotto in Florence’s Boboli Gardens for example which dates from 1583-93 has walls covered with stalactites and stalagmites, sponges, stones, and shells; in fact these are not real but were carved by the sculptor Pietro Mati. The fashion for such follies soon spread and in 1624 James I had a ‘shell grotto’ created in the undercroft of the Banqueting Hall in Whitehall. It has long since disappeared and today the oldest extant shell grotto in England is at Woburn Abbey, Bedfordshire which dates from the late 1620s onwards. By the start of the 18th century, the Shell House obsession was widespread and unlike the artifice of the Boboli Gardens, these used real shells. In 1725 poet Alexander Pope built a grotto in the tunnel linking his house and garden at Twickenham. Decorated with shells, glass and mirror shards when completed the grotto was so lovely that the poet sighed, ‘Were it to have nymphs as well it would be complete in everything.’ No wonder therefore that around this time the creation of Shell Houses also began to be popular in Ireland.

One of the few extant 18th century Shell Houses in Ireland can be found in the grounds of Curraghmore, County Waterford. As was so often the case, the exterior of the building gives little indication of the richness found within. It has, as noted by James Howley (The Follies and Garden Buildings of Ireland, 1993) the cruciform plan of a miniature baroque church, with walls built of uncut but slightly rounded stones and a stone-flagged roof. As Howley goes on to explain, the interior ‘contains an Aladdin’s cave of rich, shell-encrusted detail on a series of interlocking domed spaces. These are arranged axially around the largest central space, with three circular apses, each containing a window and a small rectangular entrance lobby. Niches are placed between the entrances to the apses and the entire plan is knitted together by an elaborate floor pattern of great intricacy worked in pebbles.’ In the centre of the shell house stands a life-size white marble statue by John van Nost representing the woman responsible for its creation: Catherine, Countess of Tyrone. Most helpfully, a scroll carried in her right hand (her left appropriately holds a conch shell) informs readers ‘In two hundred & sixty one days these shells were put up by the proper hands of the Rt. Hon. Cathne Countess of Tyrone 1754.’ Finding the shells was a time-consuming, and potentially expensive, business, and involved liaising with sea captains and ship owners whose vessels would have returned from overseas voyages. Many of those used at Curraghmore are believed to have been acquired in the port of nearby Waterford city. And planning the design so that it formed a coherent whole would also have been an arduous process: only when sufficient materials had been gathered could the work of putting them into place commence. Seemingly the glue used for fixing the shells into place was a mixture of ox blood and hooves (presumably boiled down). It served the purpose well since most of them remain in place, thereby allowing us to appreciate this rare surviving example of a Irish Georgian shell house.