The coalfield extends along the coast from Whitehaven to Maryport, a distance of fourteen miles, and varies in width from four to six miles. From Maryport it continues a further twelve miles to Wigton, but narrows to about two miles in width. In addition a large area of coal has been worked under the sea bed, mostly in the Whitehaven area, with the coal being mined up to four miles out from the coast.
There are seven principal coal seams in the Whitehaven area:
- Upper Metal Band – 3ft 6ins wide, at 48 fathoms deep (at Wellington Pit)
- Preston Isle Yard (Burnt) – 2ft 6ins wide, at 53 fathoms deep
- Bannock – 6ft wide, at 74 fathoms deep
- Main Prior – 9ft wide, at 96 fathoms deep
- Little Main – 2ft wide, at 127 fathoms deep
- Six Quarters – 6ft wide, at 139 fathoms deep
- Four Feet – 2ft 3ins wide, at 187 fathoms deep
The dip of all the above seams is seaward, with a fall of approximately 1 in 2. The Main seam crops out near the line of the low road to St.Bees, and has been worked from a very early period along the outcrop as far as Partis Pit near Stanley Road, Mirehouse. The Bannock seam crops out at a correspondingly higher level.
At first the coal was worked from the outcrops where the seam was exposed. One of the earliest records of coal mining in West Cumberland dates to 1560 when Sir Thomas Chaloner, lord of the manor of St Bees,in granting certain leases within the manor, reserved for himself the right to dig for coals while at the same time granting his lessees liberty to take coals from his pits for their own use, on the condition that they paid and laboured from time to time therein, according to the custom of the manor.
The Lowther Family came on the scene in the 1600s, in particular Sir John who may truly be described as the founder of the Whitehaven collieries. These were worked by the Lowthers – ably assisted by their agents, the Speddings – till August 1888, when the working pits and a large tract of submarine coal were leased to the Whitehaven Colliery Company. The mines stayed in private hands till the industry was nationalised in 1947.
A major development in coal mining took place in West Cumberland in 1650 when, to win new tracts of coal, pits were sunk and drifts cut horizontally from the lower grounds to drain the workings. This arrangement was called the pit and adit system. The coal was originally raised by jackrolls and later by horse gins.
In 1663 Sir John Lowther drove a long level from Pow Beck in a westerly direction under Monkwray and into the Bannock Seam. This level drained an area sufficient to serve the needs of the coal trade until nearly the close of the 17th century. Later, on the 10th November 1715, in order to win coal from deeper levels, Lowther installed the first steam pumping engine in a Cumberland mine at Stone Pit, Howgill near Whitehaven. This Newcomen engine, with a 17 ins cylinder, was hired for £182 per annum.
Another great feat took place in 1729 when the Lowthers started sinking Saltom Pit right on the sea shore, just clear of the cliffs. The sinking of this new mine so close to the sea, to work the coal under the sea bed, was quoted as being the most remarkable colliery enterprise of its day. When the pit had been sunk 252 feet a strong blower of gas was pricked, then piped to the pit top where it burned for many years. The agent, Mr Spedding, offered to supply the gas to the town of Whitehaven but the trustees did not take up his offer.
Throughout their history the coal mines of West Cumberland, and in particular those in the Whitehaven area, were plagued with firedamp (CH4), and as greated depths were reached the problem of ventilation became critical. Accumulations of gas precipitated explosions which killed or maimed the colliers and seriously damaged the underground workings. To the employer the damage done to the mines was more important than the loss of life.
New methods of lighting and ventilation were tried. One of the most important early inventions was the Spedding steel mill, the first attempt to produce a safe means of lighting in an atmosphere containing firedamp. This new device was merely a steel disc fixed to a small cogwheel and geared to a larger wheel. When the handle was turned a piece of flint was held against the disc, creating a stream of sparks which enabled the miners to see to work. The use of the Spedding steel mill spread throughout the north of England, and they were used till the introduction of the Davy lamp in 1819.
Wooden props were the main means of supporting coal workings, but at the pit bottoms and main haulage roads and junctions brick walls were built and roofed in timber, second-hand steel and old tramlines. The timbers used in the Whitehaven mines of 1750 were imported from Norway by Sir James Lowther. Some of them are still supporting the old workings.