Agriculture in the United Kingdom sixfold by 1650. Improvements in transport, particularly along rivers and coasts, brought beef and dairy products from the north of England to London. The Kingdom of Great Britain was created on 1 May 1707, as a result of the Acts of Union putting into effect the terms of the Treaty of Union. At this time, Jethro Tull, a Berkshire farmer, had recently invented his famous rotating-cylinder seed drill. His 1731 book, "The New Horse Hoeing Husbandry", explained the systems and devices he espoused to improve agriculture. The book had such an impact that its influence can still be seen in
Drill bit shank shank was common before 1850, and is still in production. At first, the tapered shank was just rammed into a square hole in the end of the drill. Over time, various chuck designs have been invented, and modern chucks can grasp and drive this shank effectively. It has been difficult to find a reference to the included angle of the taper, but 7 different bits were measured, and they all had an included angle of 8 ± 0.25 degrees. The straight shank is the most usual style on modern drill bits, by number manufactured. The whole of the drill bit,