Adam Heslop Winding Engine
Adam Heslop and his Winding Engine
At the William Pit
Work began to sink the William Pit in 1804 on the northern shore at Whitehaven in Cumbria; the necessity to sink this pit was to extract the coal from the rich seams that extended beneath the Irish Sea. The first baskets (corves) loaded with coal were hauled to the surface by Adam Heslop’s winding engine on the 10th March 1806. The mine was in continuous production until closure in 1954; by this time the workings had extended for almost three miles under the sea.
The William Pit in 1814 was described as “The most dangerous pit in the kingdom” because throughout the
An original small corf which can be seen preserved at the Caphouse Museum near Wakefield. Shown on the engine in miniature the loaded corves are being transferred onto a track before being hauled to the surface by Adam Heslop’s winding engine.
The danger in this and many other mines accelerated the development of Humphry Davey’s safety Lamp and, in about 1816 this lamp was first used at the William Pit for trials. This area of Cumbria had rich deposits of coal which extended for almost a hundred square miles, with mining taking place from Whitehaven, to beneath the Solway Estuary.
A replica of the Spedding Mill which was rotated throughout a working day by boys from the age of eight.
Sinking of the Pit
Sinking commenced in May 1804 and by March 1805 the shaft had reached a depth of 552 feet, this being an average descent of twelve feet per week. The final depth was 630 feet, and the shaft had a diameter of fifteen feet. This was accomplished in appalling conditions by men using only hand tools, however; when hard rock was encountered the assistance of gunpowder became necessary. The spoil from the shaft was brought to the surface by horse powered gins with forty gallons held in each tub. In total more than 55,000 loads were removed.
When the full depth had been reached, the shaft, was lined from top to bottom with timber, and then divided into three sections, two for the winding of miners and coal, and the third for removing the flood water from the mine workings. In the Cumberland Pacquet Newspaper on the 26th March 1805 was written how this remarkable achievement was completed.
The first engine to be used at the William Pit was made to the design of Adam Heslop, a design he had patented in 1790. This engine which became patent number 1760 stated that his method of operation “lessened the consumption of steam and fuel in fire-engines or steam engines”.
The engine that was assembled had two cylinders; which were powered by the weight of the earth’s atmosphere. Steam was used as a means of creating a vacuum on the underside of each piston; making this a double acting atmospheric engine. One powering cylinder (the hot cylinder) was 44 inches in diameter and used both the expansive force of steam and a vacuum on the underside of the piston; the other cylinder (the cold cylinder) was 28 inches in diameter, and operated with a constant vacuum on the underside of the piston.
This unique method of operation was ideally suited to a winding engine, because, powered in this way it became self-starting. And with some clever positioning of the crank, by the operator, the engine also became self-reversing.
The William Pit engine was made at the Lowca Ironworks of Heslop, Millward and Johnston. From 1800 brothers Adam, Thomas and Crosby Heslop operated from this site supplying atmospheric engines to the northern collieries, and over the next ten years fourteen engines are recorded to have been made. Many of Heslop’s engines had long working lives; three were working at collieries in Shropshire for almost 100 years.
The engines designed by Adam Heslop were successful and this one at the William Pit operated from 10th March 1806 until it was superseded in 1850 by a high pressure engine this was more efficient and provided more power.
William Danniell’s aquatint painted in 1814 showing the harbour at Whitehaven with the William Pit in the background.
This photograph shows the completed engine built to
Shown here are the engine and boiler, with the oscillating beam within the tiled roof of the building. The chimney shown here has been lowered; if this had been built exactly to scale the model would have proved difficult and not easily removed from my workshop. The floor of the model is covered with slabs of micaceous sandstone from a quarry at Bollington in Cheshire these were cut to size with a diamond slitting saw, and surrounding the furnace can be seen engineering blue bricks all made to the scale of ¾ inch to one foot.
The hot cylinder for the engine in miniature, machined from a solid piece of mild steel, now measuring 3 inches in diameter. Also shown is the flywheel machined from a solid blank with a diameter of 15 inches
STARTING THE ENGINE WITH AN EMPTY BOILER
An intense fire would have been needed, and when the water had reached the boiling point, and the steam had reached a working pressure 3 p.s.i., (0.2 bar) the operator would have manipulated the levers, first he closed the valve at the base of the hot cylinder (7) by closing this and opening valve (8) the steam was directed into the condenser, and also filling the void beneath the piston of the cold cylinder. When this was taking place the air within the system would have been escaping through the blow valve (15) with all the air expelled and replaced by steam, the operator closed valve (8) and initiated both water sprays, one into the condenser and the other into the cold cylinder, (levers 46) a vacuum had now been created, it was generally accepted with an engine in good workng condition that a vacuum of 0.6 bar could be achieved, this equating to a working pressure of 9 p.s.i., and when acting upon a cylinder of 28 ½ diameter would have exerted a downward force of 2.5 tons (2,500 kg).
The cold cylinder was unable to move the engine because the space beneath the piston in the hot cylinder was sealed. The operator then ensured that the crank was in the position shown in the schematic diagram ie. if the basket was to be lowered into the mine. By opening valve (7) low-pressure steam was allowed to fill the space beneath the piston in the hot cylinder, 3 p.s.i., exerting an upward force of 2.0 tons this combined with the load exerted by cold cylinder started the engine rotating in an anti-clockwise direction. On the completion of the first revolution the hot cylinder was powered vertically by low pressure steam and on the downward stroke by a vacuum onto the underside of the piston from the condenser.
With the coal loaded into the basket and with the crank in the oposite position the engine would now rotate in a clockwise direction and haul the basket to the surface. There as been much speculation and discussion about how Adam Heslop reversed his engine, many scholars saying they were unable to discover the mechanism he used, there was no mechanism, the direction of rotation all depended upon the position the crank had been brought to rest.
This concludes my story about the William Pit and Adam Heslop’s winding engine all brought about in my quest to research this unique engine and fully understand by constructing the engine in miniature how it operated in 1806, and by doing ensure Adam Heslop the credit he so richly deserves.