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 is evaluated as well. These new drill instructors bear the burden of responsibility for breaking down a recruit's sense of self and selfishness, so that the more experienced drill instructors can focus the recruits on selflessness, obedience, and fraternity. After completing a few 13-week cycles, the drill instructor is moved up to the position of "Experienced Drill Instructor" (EDI), also called the "heavy", "drill hat" or "J Hat". The next step in a drill instructor career is becoming a "Senior Drill Instructor". Senior Drill Instructors hold a respected position which is distinguished by the wearing of a black