Potash pits were kiln sites which were dug and lined with drystone walling for the production of

potash Potash ( ) includes various mined and manufactured salts that contain potassium in water- soluble form.

Industrial Revolution The Industrial Revolution, sometimes divided into the First Industrial Revolution and Second Industrial Revolution, was a transitional period of the global economy toward more widespread, efficient and stable manufacturing processes, succee ...

. The scouring or degreasing of the natural

lanolin Lanolin (from Latin 'wool', and 'oil'), also called wool fat, wool yolk, wool wax, sheep grease, sheep yolk, or wool grease, is a wax secreted by the sebaceous glands of wool-bearing animals. Lanolin used by humans comes from domestic sheep br ...

from wool requires the application of soft soap produced using fat and an alkaline potash solution that contains water-soluble

potassium Potassium is a chemical element; it has Symbol (chemistry), symbol K (from Neo-Latin ) and atomic number19. It is a silvery white metal that is soft enough to easily cut with a knife. Potassium metal reacts rapidly with atmospheric oxygen to ...

salts such as potassium carbonate and potassium hydroxide.Potash
USGS 2008 Minerals Yearbook

Purpose

The potash pit was a basic stone lined ashery in which hardwoods such as

birch A birch is a thin-leaved deciduous hardwood tree of the genus ''Betula'' (), in the family Betulaceae, which also includes alders, hazels, and hornbeams. It is closely related to the beech- oak family Fagaceae. The genus ''Betula'' contains 3 ...

wood or

bracken Bracken (''Pteridium'') is a genus of large, coarse ferns in the family (biology), family Dennstaedtiaceae. Ferns (Pteridophyta) are vascular plants that undergo alternation of generations, having both large plants that produce spores and small ...

were burned to produce ashes which were then placed in a copper cauldron manufactured from strips of copper and boiled together with water and

quicklime Calcium oxide (formula: Ca O), commonly known as quicklime or burnt lime, is a widely used chemical compound. It is a white, caustic, alkaline, crystalline solid at room temperature. The broadly used term '' lime'' connotes calcium-containin ...

. The

alkaline In chemistry, an alkali (; from the Arabic word , ) is a basic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water. A solution of a soluble base has a pH greater than 7.0. The ...

solution produced by the ashes and added quicklime could be filtered to remove particles and once the required alkalinity was reached fats were added to produce a soft soap for the scouring or degreasing of the wool as a vital step in the production of wool for spinning into yarn.

Location

Many potash pits were built in or near areas of suitable

deciduous In the fields of horticulture and botany, the term deciduous () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed Leaf, leaves, usually in the autumn; to the shedding of petals, aft ...

woodlands and as such they are an important landscape features indicating both the processing of wool and the presence of a suitable hardwood

woodland A woodland () is, in the broad sense, land covered with woody plants (trees and shrubs), or in a narrow sense, synonymous with wood (or in the U.S., the '' plurale tantum'' woods), a low-density forest forming open habitats with plenty of sunli ...

present at the site or nearby at the time that potash pits were in use.Muir, Pages 91 - 92.

Construction

Hawk Bridge over the River Lickle - geograph

The often circular pits were built often into earthen banks and were lined with drystone walling. A tunnel fireplace was required to draw in the air for the burning conversion of the birch, bracken, etc. into ashes, used for heating the cauldron as well as the source of the potash.Hawksley, Page 46

Geographical location

The pits are a feature found in sheep farming districts with extensive woodlands such as the

Lake District The Lake District, also known as ''the Lakes'' or ''Lakeland'', is a mountainous region and National parks of the United Kingdom, national park in Cumbria, North West England. It is famous for its landscape, including its lakes, coast, and mou ...

in England. One example is located in the Lickle Valley,The Lickle Valley
Retrieved : 2013-07-28 Broughton in Furness.

Industrial archaeology

As a landscape feature, the remains of potash pits are superficially similar in appearance and location to Q-pits that were constructed to make

white coal White coal is a form of fuel produced by drying chopped wood over a fire. It differs from charcoal which is carbonised wood. White coal was used in England to melt lead ore from the mid-sixteenth to the late seventeenth centuries. It produces more ...

for use in smelting lead.

Saw pit A saw pit or sawpit is a pit over which timber is positioned to be sawed with a long two-handled saw, usually a whipsaw, by two people, one standing above the timber and the other below. It was used for producing sawn planks from tree trunks, ...

s were constructed in areas of woodland also, however they were rectangular in shape and are easily distinguished from the aforementioned.

References

;Notes ;Sources # Hawksley, L., Jenks, D., et al. ''The Magic & Mystery of the Lake District''. Bristol : Dempsey park. . # Muir, Richard (2008). ''Woods, Hedgerows and Leafy Lanes.'' Stroud : Tempus. . {{Portal, England Buildings and structures in England Archaeological sites in England History of forestry Forestry in the United Kingdom Potash