History of agriculture the New Leicester sheep. Machines were invented to improve the efficiency of various agricultural operation, such as Jethro Tull's seed drill of 1701 that mechanised seeding at the correct depth and spacing and Andrew Meikle's threshing machine of 1784. Ploughs were steadily improved, from Joseph Foljambe's Rotherham iron plough in 1730 to James Small's improved "Scots Plough" metal in 1763. In 1789 Ransomes, Sims & Jefferies was producing 86 plough models for different soils. Powered farm machinery began with Richard Trevithick's stationary steam engine, used to drive a threshing machine, in 1812. Mechanisation spread to other farm uses through the
Drill instructor Drill Instructor Ribbon, and the Army's Drill Sergeant Identification Badge. It may be taken offensively by U.S. Marine Corps Drill Instructors to be referred to as 'Drill Sergeants', which is strictly an Army term in the American military, just as Marines may take offense to being called "soldiers". This is considered to be a grievous insult if done intentionally. The only acceptable address of a drill instructor by a recruit is "sir", "ma'am" or "(senior) drill instructor (Rank) (last name)". At Officer Candidates School (OCS), candidates are instructed by Drill Instructors who have already served a tour at one of