Mechanization in 1801, displacing the centuries-old hand method of making individual sheets of paper. One of the first mechanical devices used in agriculture was the seed drill invented by Jethro Tull around 1700. The seed drill allowed more uniform spacing of seed and planting depth than hand methods, increasing yields and saving valuable seed. Mechanized agriculture greatly increased in the late eighteenth and early nineteenth centuries with horse drawn reapers and horse powered threshing machines. By the late nineteenth century steam power was applied to threshing and steam tractors appeared. Internal combustion began being used for tractors in the early twentieth
Down-the-hole drill to improve drilling rates in hard rocks. Construction- Piling, Footings Down-the-hole drill A down-the-hole drill, usually called DTH by most professionals, is basically a mini jackhammer screwed on the bottom of a drill string. The fast hammer action breaks hard rock into small flakes and dust and is blown clear by the air exhaust from the DTH hammer. The DTH hammer is one of the fastest ways to drill hard rock. Now smaller portable drillcat drilling rigs with DTH hammers can drill as fast as much larger truck rigs with this newer technology. The system is thought to have been