Seed drill China, and later a seed drill by Jethro Tull that was influential in the growth of farming technology in recent centuries. Even for a century after Tull, hand sowing of grain remained common. In older methods of planting, a field is initially prepared with a plow to a series of linear cuts known as "furrows". The field is then seeded by throwing the seeds over the field, a method known as "manual broadcasting". The seeds may not be sown to the right depth nor the proper distance from one another. Seeds that land in the furrows have better protection from
Core drill Core drill A core drill is a drill specifically designed to remove a cylinder of material, much like a hole saw. The material left inside the drill bit is referred to as the "core". Core drills used in metal are called annular cutters. Core drills used for concrete are generally called Diamond Core Drills and are water cooled. For drilling masonry, carbide core drills can be used. The earliest core drills were those used by the ancient Egyptians, invented in 3000 BC. Core drills are used for many applications, either where the core needs to be preserved (the drilling apparatus