23673

 

II  

Designated  

21/07/2000  

21/07/2000  

Engine and Compressor House  

 

Gwynedd  

Llanllyfni  

Caernarfon  

Pen-yr-Orsedd  

250977  

354185  

 

Located on Level VIII (Bonc Brig) of the Pen-yr-Orsedd Slate Quarry towards the foot of the modern steep access road from Y Fron.  

Industrial  

 

Engine and compressor house built in the early C20 as part of a major phase of investment in the quarry, which saw the introduction of alternating current electricity from Cwm Dyli power station to operate the blondin ropeway system, which was established to take material from the new deep slate pits being formed at this time: the engine and compressor house powered this ropeway system. The quarry opened c1816 and in 1863 it was bought by W A Darbishire & Co. During the 1890s about 450 men worked here: it finally closed in 1997.  

Regularly coursed slate slabs with some roughly coursed rubblestone; slate roof with purple brick stack in roof slope to long wall on front. Engine house of rectangular plan with lean-tos attached to left gable end and to front on right, the latter being the compressor house. Boarded door and 6-paned window to right gable end of engine house. Associated with a collapsed blondin ropeway system.  

The engine house has its winding drums, operated from a Bruce Peebles 3-phase motor of 1906 through reduction gearing, of which the motor, control mechanism and the liquid controller survive. The compressor house contains an electric motor and a horizontal single-cylinder Ingersoll Sargeant air compressor and receiving chamber.  

Included as an early C20 engine house and compressor house retaining its original machinery, important for the evidence it provides of the pioneering new technology being introduced to the quarry at this period; group value with other structures on Level VIII. Scheduled Ancient Monument (208).