Archaeological digs off the Co Antrim coast are turning up remarkable evidence of Stone Age tool making, writes Dick Ahlstrom.
Rathlin Island, off the Co Antrim coast, has an ancient industrial history. In Neolithic times, 7,000 years ago, it had a stone-tool factory; more recently, in the 18th and 19th centuries, its kelp kilns produced bleaches for Northern Ireland's linen makers. These and other findings come from a survey of Rathlin's archaeology by the University of Ulster's centre for maritime archaeology, in Coleraine.
The centre's 15 to 20 academics, researchers and postgraduates conduct a wide range of research work, from coastal digs through sonar surveys of 400-year-old shipwrecks. The centre has conducted a number of coastal surveys, with Strangford Lough a recent example, according to Wes Forsythe, one of the centre's maritime archaeologists. They identified 600 sites of archaeological interest on the lough, he says, from ancient middens, or waste dumps, to clusters of huts and stone structures used as fish traps.
"Rathlin is the next area we are taking on. It is very different to Strangford," says Forsythe. The tidal lough presents a much less turbulent coastline, with less damage to old structures. Rathlin, which covers 3,500 acres four kilometres from Fair Head and 23 kilometres from the Mull of Kintyre, is a much tougher environment. Powerful tides and storm swells pull at the coastline and any remains it might hide.
Much of the island offers boulder-strewn bedrock and tall cliffs along its coastal margins - hardly hospitable for Mesolithic or Neolithic remains. "We took it on because we wanted a contrast with what we saw at Strangford," says Forsythe. Even so, Rathlin is already giving up its secrets, with 200 sites of interest discovered in the past two years, he says. "What we are mainly finding is that the archaeological remains aren't in the intertidal range but farther up the shoreline." Their finds include timber works dating back several hundred years. "The majority of sites have been post-medieval in nature," he says. They include landing places and shelters for boats and small docks.
Unexpectedly, the tough cliff faces are also providing sites of interest. "Below the cliffs we are getting a lot of material related to the linen industry," says Forsythe.
Rathlin was long known as a processing centre for kelp, which was first dried, then burned in small kilns to produce bleaching agents. Up to 150 kilns reportedly existed in the mid-19th century; the survey has uncovered 81 of them so far. Historical records indicate that as far back as 1784 linen processors bought all the kelp available on Rathlin for their cloth trade.
The linen industry died down, but the kilns had a brief resurgence, Forsythe adds, when kelp began to be processed for iodine. It found its way first into medicines and, in the early 20th century, the growing demand for photographic equipment.
The remains of kilns and low drying walls are found on terracing below the cliffs, testimony to this changing trade.
Rathlin had a much earlier period of industrial activity, as a centre for the production of a very hard flint-like stone for Neolithic hand tools. "Rathlin is very well known in archaeological terms because of its porcellanite factory," says Forsythe.
Rathlin had a good supply of porcellanite - a very hard volcanic rock - which locals mined for tools. They chipped pieces of the stone into the rough shape of a tool, then shipped them off to be finished elsewhere. "We do have some finished porcellanite from Rathlin, and some of these flint blades are associated with this \ period," says Forsythe.
Only last month the researchers were excavating caves along the cliffs when they found evidence of early medieval material, including a jet bracelet and a bronze ring. Digging deeper, they encountered still earlier Bronze Age pottery. "We have two \ horizons for the caves," says Forsythe. Bronze Age burial grounds were also found on the island. "It all adds that bit more to the archaeological picture of Rathlin."