Seed drill further refined by Jethro Tull in 1701 in the Agricultural Revolution. However, seed drills of this and successive types were both expensive and unreliable, as well as fragile. Seed drills would not come into widespread use in Europe until the mid to late 19th century, when manufacturing advances such as machine tools, die forging and metal stamping allowed large scale precision manufacturing of metal parts. Early drills were small enough to be pulled by a single horse, and many of these remained in use into the 1930s. The availability of steam, and later gasoline tractors, however, saw the development of
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