At the beginning of the seventeenth century the method of manufacturing glass in northern Europe had not changed since the Middle Ages. However, by the end of the century the advances in the glass industry had made the earlier technology obsolete. The main evidence for the manufacture of glass in this period comes from medieval documentary sources because the survival rate of glass-furnaces is very poor. In England there is no surviving upstanding forest glass wood-fired furnace of the sixteenth-seventeenth-century period, and several which have been excavated only survived to a few courses high. The discovery of an extant furnace with barrel-vaulted roof in situ in the town land of Glasshouse near the village of Shinrone in County Offaly offers the archaeologist a rare opportunity to examine the technology of an often-forgotten glass industry.

Two locational factors were necessary for establishing a glass-furnace: firstly, close proximity to woodlands where there was an abundant supply of fuel and ash from the burning process; secondly, a convenient source of sand, e.g. an esker ridge. The furnaces themselves were simple rubble-stone structures consisting of a barrel-vaulted firing chamber with a central fire-trench. The fire was fed from either one or both sides of the chamber via a stoking tunnel. The crucibles were placed in pairs on top of the sieges, which were located on either side of the fire-trench. Work holes (glory holes) were built into the side of the vault to allow the glass-makers to remove impurities which rise to the surface of the molten glass and also to check when the glass was ready for working. An iron pole was inserted into the crucible via the work hole, if the molten glass was ready a thread of glass would hang from the rod.

The resulting glass was green because of potassium oxide specifically found in wood, and was known as forest glass. Dry wood, producing little smoke, was essential as there no chimney to allow smoke to escape in the furnace. Moreover, it has the additional benefit of reaching higher temperatures. The furnace itself was enclosed by a wooden building or glasshouse, some examples of which were known to have been roofed with wooden shingles or slate. The post-holes or ditches of these buildings have been identified in excavations of forest furnaces in England.

Until the mid-sixteenth century the glass industry in England and Ireland was virtually non-existent, glass being imported from France. As an example of how precious glass was at that time, it is recommended that "when Duke of Northumberland left Alnwick castle the steward was accustomed to take out the glazed windows and stow them away safely until the Duke's return". In 1567 a Huguenot, Jean Carre, obtained a permit from Queen Elizabeth I to establish a forest glass industry in the Sussex/Surrey region. The workforce was recruited from experienced glass-making families centered in the Lorraine region. Among those recruited were the Hennezells (Henseys) and the de Bigaults/Bigots (Bigos).

In 1586 Queen Elizabeth I granted Captain Woodhouse suit for a privilege to make glass in Ireland. His assistance to George Longe and Ralph Pillying in erecting and maintaining two houses for glass making'. This was followed by the granting of a monopoly in 1589. In October 1589, a petition from George Longe to Lord Burghley stated that 'he has spent his time wholly in the trade and has found stuffe meet and brought to perfection the making of glass in Ireland'. Longe had bought the patent for glass-making from Captain Woodhouse in that same year. There are also references to land being granted to Philip de Bigo in County Offaly during the Elizabethan period.

By the early seventeenth century English manufacturers had developed coal-fired furnaces based in towns which were beginning to replace the wood-fired furnaces. An Englishman, Admiral Sir Robert Mansell, held the monopoly on this new technology. Furthermore, owing to the enormous depletion of woodland a royal proclamation in 1615 banned the use of wood fuel in glasshouses in England. The increased competition of Mansell, who also ensured the strict enforcement of the 1615 ban, pushed the French families out of the glass-making industry. In order to ply their trade, some of these French families moved to other countries which were not prohibited from using wood, Ireland included.

In 1619 Mansell issued an arrest for Sir William Clavell and Abraham Bigo. This may have been as a result of Clavell and Bigo's joint venture to establish a glasshouse at Church Knowle in Dorset in 1618. Four years later, in 1623, Abraham Bigo appears in Birr, Co. Offaly, having leased land from Lawrence Parsons to construct a glasshouse in the townland of Clonbrone, near Birr. Under the conditions of this lease Bigo could not 'set up any glass house or glasswork on any other land, or buy wood of any other for his glasswork but only of me'. In the reign of Charles II (1660-85) a namesake and descendant of the earlier Philip Bigo was granted land in Ballyneshragh, Carrowmore, Feddane and Newtown in Lusmagh, Co. Offaly, and according to local tradition he established some glasshouses in these areas.

In 1638/9 the exportation and manufacture of glass in Ireland was prohibited, and in 1641 another bill prohibited the felling of trees as a fuel supply for glass-furnaces. As happened in England twenty years earlier, the combined effects of the legislation and technological advances heralded the end of the forest glass wood-fired furnaces.

The Henseys are mentioned in Ireland in the seventeenth century in Garrycastle and Banagher in the parish of Lusmagh; Kilorney, Ballyengowne, Galrus, Ballyshane in Rynagh parish; Bollinure, Ballinkellin in Shinrone parish and Clonlisk, Ballintoren, Adrowle, Kellogs in the parish of Kilcommon, Co. Offaly. On the current edition of Ordnance Survey map the latter three townlands surround the Glasshouse site, which suggests that the furnace was associated with the Hensey family. In 1670 one Ananias Hensey set up a glasshouse near the new town of Portarlington, which was founded in 1666. The Calendar of State Papers for November 1670 states that Hensey was 'failing in his art of making glass' despite the fact that he had 'practiced it in another place these twenty years past'. Perhaps Hensey was trying by trial and error to make the transition from the old wood-fired furnace to the more efficient new technology of the coal-fired furnace. The site of this glasshouse may have been located at the 'Glasshouse' marked on the Ordnance Survey map west of the town.

In England the majority of glasshouse sites have been identified by the field-name Glasshouse, and of those identified only the lower portions of the furnaces survive. Two townlands in County Offaly are called Glasshouse. The earliest reference to the townland name of Glasshouse at Shinrone was made in 1717, which suggests that the townland received its name in the seventeenth century. Townland, close to the village of Shinrone, was found, after field inspection, to contain the upstanding remains of a seventeenth-century glass furnace. This is a typical barrel-vaulted crude sandstone structure with a central fire-trench and opposing stoking tunnels. The entire internal surface of the vaulted furnace is covered in a layer of blue/green glass. There are two work holes on one side wall at the springing level of the arch, and evidence of two destroyed holes on the opposite wall. The siege platforms are in place but the end walls do not survive.

The plan and section of this furnace correspond well with a mid-sixteenth-century forest glass-furnace at Blunden's Wood, Surrey, England (see section), and a seventeenth-century example at Jamestown, Virgina, America, dated to 1608. A large fragment of another glass-furnace with similar glass-covered surface was recovered from a field wall, along with fragments of glass, in the townland of Glaster, near Lusmagh. This site is associated with Philip Bigo in the 1659 census. The furnace at Glasshouse, Shinrone, is likely to fall within the date range 1590 - 1640, based on parallels with the above-mentioned furnaces. After the 1640s the wood-fired -furnaces were replaced by the technologically advanced, town-based, coal-fired furnaces. From the Elizabethan period up to the 1659 census both the Bigo and Hensey families were known to be living and plying their trade throughout County Offaly.

Acknowledgements:
We would like to express our thanks to the following people who generously gave their time and assistance in the preparation of this article: Mary Boydell, Annette Camier, Hon. Sec. of the Huguenot Society of Ireland, David Crossley, Sheffield University and Noel McMahon, Shinrone.

Archaeology- A Window On The Hidden Past

Before the arrival of Christianity, we have no history or written record of our past and it is to archaeology, mainly, that we must look for answers about a time known to scientists as the prehistoric period. New discoveries can lead to reappraisals of the past and it is for this reason that we must treasure our archaeological monuments as they represent a finite and non-renewable resource.

Our knowledge about the past is mainly based on information from our monuments, either through excavation or survey. Such work and discoveries can often lead to new ideas and very often change our perspective on the past. The archaeological world, for academic purposes, has divided our past into periods of time each of which posses a characteristic range of artefacts and field monuments left behind by a community. These periods are: The Mesolithic or Middle Stone Age (7,000 to 4,000 BC); The Neolithic or New Stone Age (4,000 to 2,400 BC); Copper Age (2,400 to 2,200 BC); Bronze Age (2,200 BC to 600 BC); Iron Age (600 BC to 400 AD); During each period, humans have continuously evolved and as they progressed, new technologies and breakthroughs resulted in the creation of new artifacts and monuments which in their own way stand as a

However, a lot of archaeology is hidden beneath the surface of the ground and will only come to light during land building, land drainage etc. Very often discoveries made during these developments lead archaeologists to a whole new understanding on the origins and lifestyle of a community in a specific region. One such event occurred near Kilcormac in the 1970s

The Early Stone Age In Offaly- Hunter-Gatherer Society

The story of the Mesolithic site at Lough Boora is a fine example of how new discoveries can result in a radical rewriting of history. In the late 1970s, archaeologists working in Boora bog, near Kilcormac uncovered evidence of a lakeshore settlement dating from the Mesolithic period (7,000 BC) Before this discovery, the earliest evidence of humans in Ireland came from a Mesolithic site at Mount Sandel in Co. Down. Because of its coastal location, archaeologists initially speculated that early humans came from Europe and settled along the coastline as the interior of the country was impenetrable due to the dense forests. The Lough Boora site changed all that. Dated between 7,000 BC and 6,500 BC, the finds at the site proved instead that people had frequented this part of the country for up to 9,000 years.

The site, in the townland of Broughal, appears to have been located on a lakeshore, formerly sealed by peat and subsequently inundated by the modern lake. These early people lived in small circular huts constructed from saplings inserted into the ground and bent over to form a dome-shaped timber structure.

The structure was then covered with hides and other materials with a hearth or fireplace in the centre. The majority of their tools were made from a local black stone known as chert, which, like flint, is durable and produces a sharp edge. Dr Michael Ryan, who excavated the site in Lough Boora, told a Bord Na Mona conference a number of years ago: "All the hearths consisted of were patches of noticeably darker soil, rich in charcoal with little flakes of burnt bone, predominantly of immature pig but also of some wildfowl and of eels. Mixed in with that were very tiny, beautifully worked tools of a black stone, chert.

"We passed all this material, about 2,000 square metres of it through sieves as well as excavating it carefully by hand and we recovered about 1,500 artefacts of which about 200 were so called microliths."

Excavations carried out by the National Museum uncovered evidence of the diet of these early people. They ate wild pig, wood pigeon, brown trout, eel and hazelnuts.

The evidence suggest in this period, small communities lived in hunter-gatherer type societies, gathering what they could from their environment. Here our ancient ancestors caught salmon and eels in the nearby lakes and hunted pigs in the surrounding forests which at that stage covered much of the countryside. Archaeologists have no evidence yet of how Mesolithic man buried their dead and there are still a range of other questions about how they lived which have yet to be answered.

Future archaeological discoveries like Lough Boora may answer these unresolved queries. It may even be the case that the key to unlocking these mysteries remains buried deep in Offaly's bog. Maybe, too, some day, we will find earlier evidence of human settlement in the county. Whatever the case, what is certain is the significance of Lough Boora. Speaking at a Lough Boora Parklands Summer season of events two years ago, Dr John Feehan claimed that the Mesolithic site was of European significance.

"It is one of the key sites in the story of the colonisation and development of North Western Europe," he remarked.
"It's the only hugely significant Mesolithic site in this part of the island that you can see. It's the beginning of the story. This is Chapter One. This is when the book opens not just on the history of the Midlands but on Irish history."

The New Stone Age - The Spread Of Tombs

Around 4,000 BC, Irish society evolved from hunter-gatherer activity to farming. This involved the introduction of domesticated animals and crops and is known as the Neolithic period or the new stone age.
This era witnessed the appearance of a whole range of new monuments on the landscape, the best known of which are the famous megalithic tombs of Newgrange in Co. Meath.

Burial monuments of various shapes and sizes constructed from large stones (megaliths) were covered by a mound of earth or stone. Four types of megalithic tombs have been identified by archaeologists to date, court tombs, portal tombs, passage tombs, wedge tombs. These are categorised on the basis of the ground plan and form of the tomb.

There is little evidence for any of these tombs in Offaly or indeed of Neolithic sites in the county. However, it has been suggested that the mound on Croghan Hill and the large burial mound at Forelacka in the Slieve Bloom mountains may conceal megalithic tombs.

Court Tombs: These are possibly the earliest example of the megalithic tomb in Ireland and consist of two, three or four chambers with an open roofless courtyard, usually located at the east end of the tomb and covered by a mound of earth or stone. The majority of these are in the northern half of the country although there is a fine example at Shanballyedmond, Rearcross, Co. Tipperary.

Portal Tombs: Usually referred to as dolmens, these are the most distinctive type of tombs. They consist of two large upright side stones and a back stone which supports a huge often impressive, capstone sloping from back to front. The dolmen from Poulnabrone, Co. Clare is probably one of Ireland's best known monuments from its association with Guinness advertisement.
Passage Tombs: Consisting of a chamber, or chambers, they are usually accessed from a narrow passage contained within a large mound of earth or stone, with a retaining wall around the base of the mound often decorated with spiral patterns.
The Boyne Valley in Meath contains the most impressive collection of passage tombs in Ireland.
Wedge Tombs: Classified according to the distinctive wedge-shape of the usually large burial chamber, there is often a smaller chamber preceding the main chamber and the whole monument is usually covered by a large earthen or stone mound.

These tombs often appear in the landscape without their covering mound which has been worn away by nature over several millennia.

There are two possible megalithic tombs in Offaly located in the Slieve Bloom mountains but because of their poor state of preservation it is impossible to classify them precisely. They are located at Ballywilliam in the barony of Ballybritt and Gorraun in Clonlisk barony.

Large burial mounds, which are found throughout Offaly, may contain examples of some of the burial tombs described above, or even a new type of tomb, yet to be identified.
It has been speculated that the mound on Croghan Hill (see picture below) may date to the Neolithic period and may be an example of a burial mound covering a tomb.

The mound on Croghan Hill, on right of picture, may date to the Neolithic period and may be an example of a burial mound covering a tomb

Similarly, the large burial mound at Forelacka (see picture) in the Slieve Bloom mountains could be the site of a passage tomb. It size and the presence of kerbing around the base have heightened such speculation.

The large burial mound at Forelacka in the Slieve Bloom mountains could be the site of a passage tomb. It's size and the presence of kerbing around the base have heightened such speculation.

Other monuments belonging to this period include the field and wall systems found underneath blanket bogs. Such a discovery has been made at the Céide fields in Co. Mayo in recent years and it is possible that such early field systems also await discovery under the blanket bogs of the Slieve Blooms.

House sites have also been discovered from this period, usually during excavation.
Recent infrastructural development work such as road building, has led recently, to the discovery of new Neolithic sites, though to date, none have been discovered in Offaly.

Monuments and The Law

All archaeological monuments listed in the Record of Monuments and Places which is compiled by Duchas, the Heritage Service are protected by law under Section 12 of the National Monuments (Amendment) Act.
A copy of the Record of Monuments and Places can be found in your county library.
The act stipulates that:

• No work can be carried out on or near a site listed in the record
  without two months written notice to Duchas.
  Conviction for such an offence can result in a maximum penalty of a €1,200 fine and/or twelve months imprisonment in the District Court and a maximum penalty of €63,500 and/or five years imprisonment on conviction in the Circuit Court.
• No metal detectors are allowed at or near a monument listed in the
  record.
  Conviction for such an offence can result in a maximum penalty of a €1,200 fine and/or six months imprisonment in the District Court and a maximum penalty of €63,500 and/or twelve months imprisonment on conviction in the Circuit Court.

Offaly Heritage Forum- Protecting The Past For The Future

THE Offaly Heritage Forum was set up in 2001 to produce and implement a heritage plan for the county. It is a cross-agency group facilitated by Offaly County Council. While many groups are represented on the forum, public consultation during the planning process meant that the views of many other groups were included. The members of the forum are; Cllr Eamon Dooley, Chairman, Planning and Economic Development Strategic Policy Committee, Offaly County Council; Tom Roche, member of Community Forum, Offaly County Development Board; Kevin O'Dwyer, member of Arts and Culture Group, Offaly County Development Board; Vincent Hussey/ Debbie Grey, Forward Planning, Offaly County Council; William Wall, County Engineer, Offaly County Council; Catherine Casey, Birdwatch Ireland; Perpetua McDonagh, Offaly LEADER; Steve McNeill, Offaly Historical & Archaeological Society; Christine Byrne, Slieve Bloom Rural Development; Sharon Parr, Lough Boora Parklands; Edward Delahunt, IFA; Tom Egan, Bord Na Mona Energy Ltd; John Prior, Coillte; William Dooley, Teagasc; Val Swan, Duchas, National Parks and Wildlife; Caimin O'Brien, Duchas, Built Heritage and Amanda Pedlow, Heritage Office, Offaly and Laois County Councils.

The heritage plan was adopted by Offaly County Council in December 2001 and was one of the first to be adopted in the country. The first year of implementation of the plan has been supported by finance from the Heritage Council and Offaly County Council with many of the agencies and groups also making contributions. The main activities carried out this year included a survey of thatch in Offaly, the production of a pilot village design statement ( Kilcormac), the hosting of a seminar on care of graveyards; the production of a poster of Offaly's monuments.

The heritage forum will also host a tidy towns seminar, on Tuesday next, October 29th at 8.30 p.m. in the Tullamore Court Hotel, while a pilot Tidy Towns wildlife project in Daingean is also underway.

This series of articles is taken from the 'Tullamore Tribune', Oct - Nov 2002