Gunpowder Mill Langdale Valley : 無料・フリー素材/写真
Gunpowder Mill Langdale Valley / SLR Jester
| ライセンス | クリエイティブ・コモンズ 表示 2.1 |
|---|---|
| 説明 | The manufacture of gunpowder in Cumbria developed initially in response to demand from the mining and quarrying industries of the region, making use of the natural resources of woodland and water power available in Furness and South Lakeland.Gunpowder is a mixture of saltpetre, charcoal and sulphur, usually in the proportion of 75:15:10, although these varied according to the purpose for which a particular type of powder was intended. The saltpetre, or potassium nitrate, supplies oxygen, and the other constituents provide fuel, the sulphur serving to inflame at a relatively low temperature. Saltpetre was imported from India, Chile and Germany, sulphur from Italy and Sicily, originally through the local ports of Milnthorpe or Greenodd. Charcoal was made from local woodlands initially, using juniper, silver birch and alder. The old method of charcoal burning (or rather roasting) however did not result in a clean enough product for gunpowder, and so the charcoal was burnt in retorts of a kind invented by a well-known Lakeland resident, Bishop Watson, in the eighteenth century.The general production process involved refining the saltpetre and sulphur, which then along with the charcoal were pulverised, weighed, mixed and then incorporated by grinding and crushing them into a mixture known as mill cake. This was then broken down, pressed into hard slate-like sheets of press cake, corned into grains, dusted, glazed and finally dried. This process, with particular reference to the Elterwater site, is described in detail in “The Industrial History of the Lake Counties”. The availability of water power throughout the site was crucial, although Black Beck was worked by steam engines.There were 7 works operating at times during the 18th, 19th and 20th centuries, from the opening of Old Sedgwick in 1764 to the closure of Gatebeck in 1937. |
| 撮影日 | 2006-11-04 11:12:18 |
| 撮影者 | SLR Jester |
| 撮影地 | |
| カメラ | Canon EOS 350D DIGITAL , Canon |
| 露出 | f/11.0 |
| 開放F値 | f/11.0 |
| 焦点距離 | 55 mm |