In 2005 excavations took place on the site of the present Glasshouse hotel. The site had been that of the Sligo Mills, owned by the Pollexfen family in the late 19th and early 20th century. The Pollexfens were WB Yeats maternal family.
Mills on the site appear to have been there at least since the 16th century, but probably much earlier and there may have been even earlier mills associated with the castle since the 13th century.
The milling interests owned by the Pollexfen family became a limited company in 1913 and was thereafter known as Messrs. W. & G. T. Pollexfen and Co. Ltd. The Sligo mills were located at Victoria (Hyde) Bridge and by 1926 the production output was one hundred tons of maize per day. In 1927 the Sligo Mills were closed.
The mills were an important part of the industrial history of the town, and were employers of large numbers of people. Carters, millers and numerous dock workers were involved in the business. Maize was imported to be ground here.
The mills played a colourful part in the history of the town, not always without controversy, becoming involved in the 1913 Sligo dock strike. During the strike, a particularly violent strike which involved much rioting in the town, Patrick Dunbar, a striker, of Riverside, who was employed at Pollexfen’s Mills and was a married labourer and member of the I.T.G.W.U. was assaulted and later died from his wounds during fighting between the strikers and labourers shipped in to break the strike. This led to reprisal attacks on Pollexfen’s clerical workers, when strikers broke the windows of their offices. Hundreds of police and soldiers were brought in to the town to protect property.
The mill was converted into a cold-storage facility in the 1930s.
The Mills
The mills were tidal mills, with the water at high tide supplementing the flow of the river to fill the millpond and drive the huge wheels used to power the mills. This means the mills stopped twice a day at high tide when the flow of the river effectively stopped. The millpond was upstream, and formed by the weir which extends across the river just upstream from Hyde bridge. A large part of the weir was broken down in the 1960s during the construction of the Silver Swan hotel on the site, the rubble forms the “rapids” near the bridge. This was to stop it from pushing the flow of water under the building as it was designed to do. The weir was supposed to be rebuilt, but that has not happened yet.
Archaeology
The mill was powered by three large undershot waterwheels, one external mounted to the side of the building, near where the modern side entrance to the hotel is. Two internal wheels of c. 3.8m in diameter were fed by two brick arched headraces. Two arched tailraces exited between Fish Quay and Martin’s Quay to the north. The internal race had been extended in the later 19th century to reclaim ground for the construction of ancillary mill buildings. The millraces were filled in with rubble in the 1960s during construction of the Silver Swan but survived largely intact at the time of the excavation.
The most remarkable finds were of at least seven millstones in various states, some of which are pictured here. These millstones are 4 and a half feet in width. These type of composite millstones are not very common, as they tend to fall apart and are lost once their iron binding hoop disintegrates. They were of a French type, and most likely imported from there. their composite nature allowed them to be more easily transported and assembled on site. One was in excellent condition, still bound by its iron retaining hoop. They are an important reminder of Sligos industrial heritage, but the lack of a regional museum means they cannot be displayed.
Other features found included large curved wooden sluice gates that survived in situ. These were slatted timber and at least ten feet in height and were painted with red lead that had preserved them.
Also surviving were three axle-bearing blocks with associated pit-wheel pits and a lay shaft pit (see photos), all built in ashlar (cut stone) masonry. Finds from the backfill of the pit-wheel pits were fragments of a metal axle collar. The axle blocks still contained grease from their last use.
Grooves cut into the stone by the wheels when they went off centre were visible scored into the masonry, showing the power of the wheels when in motion.
To the north of the mill building and also surviving were the near-complete structures of Fish Quay and Martin’s Quay. These stone masonry quays were built in irregular courses of squared roughly faced blocks and survived on site to a depth of 3.1m. The quays were linked by a triple-arched bridge, built off the bedrock, with two stone ashlar piers and three red and yellow brickwork segmental arches. The bridge may have been a later 19th-century rebuild of the original wooden bridge. The bridge, and sections of quay, although in good condition were demolished to make way for the underground carpark..
Two large metal casings for Leffel turbines were installed at the south-east corner of the mill as a source of power. The turbines had been removed, but remaining were the circular horizontal turbine housings, 1.54m in diameter, bolted into a wooden floor in the submerged turbine room.
At the very lowest levels, above the bedrock, remains of possible wattle structures were encountered. these were in poor condition and could not be investigated due to time constraints.
Postscript: All features surviving on the site were destroyed during the construction of the Glasshouse hotel complex. This shows the problem with granting permission for underground works prior to investigation of a site.
An attempt to retain the millstones for Sligos heritage was made, but the stones could not be transported to the current museum site because of limited access for machinery. They were subsequently supposed to be incorporated into the development, but with the financial collapse they were abandoned for a time. The lack of a museum in Sligo means they could not be retained and are currently believed to be in private hands.
© Dylan Foley 2017
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.