mine digging
41Dartmoor tin-mining — The wheelpit at Huntingdon mine The Dartmoor tin mining industry is thought to have originated in pre Roman times,[1] and continued right through to the 20th century. From the 12th century onwards tin mining was regulated by a Stannary Parliament …
42Trench warfare — is a form of warfare where both combatants have fortified positions and fighting lines are static. Trench warfare arose when a revolution in firepower was not matched by similar advances in mobility. The result was a slow and grueling form of… …
43Sough — A Sough is an underground channel for draining water out of a mine. Its ability to drain a mine depends on the bottom of the mine being higher than a neighbouring valley. If the mine sump is lower, water must be pumped up to the sough. Derbyshire …
44De re metallica —   Title page of 1556 edition …
45excavation — noun 1. the act of digging (Freq. 2) there s an interesting excavation going on near Princeton • Syn: ↑digging, ↑dig • Derivationally related forms: ↑dig (for: ↑dig), ↑ …
46Slate industry in Wales — The slate industry in Wales began during the Roman period when slate was used to roof the fort at Segontium, now Caernarfon. The slate industry grew slowly until the early 18th century, then expanded rapidly until the late 19th century, at which… …
47Battle of the Crater — Infobox Military Conflict conflict=Battle of the Crater partof=the American Civil War caption= Scene of the explosion Saturday July 30th Alfred R. Waud, artist. date=July 30, 1864 place=Petersburg, Virginia result=Confederate victory combatant1=… …
48Combat engineering — is a combat service support role of using the knowledge, tools and techniques of engineering by troops in peace and war, but specifically in combat. A combat engineer, in many armies also called pioneer or sapper, is a military specialist in… …
49Huntington, Utah — Infobox Settlement official name = Huntington, Utah settlement type = City nickname = motto = imagesize = image caption = Looking northward along Huntington s Main Street image mapsize = 250px map caption = Location of Huntington, Utah mapsize1 …
50Geophysical MASINT — is a branch of Measurement and Signature Intelligence (MASINT) that involves phenomena transmitted through the earth (ground, water, atmosphere) and manmade structures including emitted or reflected sounds, pressure waves, vibrations, and… …
