Jethro Tull (agriculturist) the seed so that it could grow. Before the introduction of the seed drill, the common practice was to plant seeds by broadcasting (evenly throwing) them across the ground by hand on the prepared soil and then lightly harrowing the soil to bury the seeds to the correct depth. In his 1731 publication Tull described how the motivation for developing the seed-drill arose from conflict with his servants. He had struggled to enforce his new methods upon them, in part because they resisted the threat to their position as labourers and their skill with the plough. Jethro Tull invented some
Down-the-hole drill for the DTH method underground, where the direction of drilling is generally upwards instead of downwards. In "DTH" drilling, the percussion mechanism – commonly called the hammer – is located directly behind the drill bit. The drill pipes transmit the necessary feed force and rotation to hammer and bit plus compressed air or fluids for the hammer and flushing of cuttings. The drill pipes are added to the drill string successively behind the hammer as the hole gets deeper. The piston strikes the impact surface of the bit directly, while the hammer casing gives straight and stable guidance of the