Tull, Jethro (1674–1741)
English writer and agronomist who invented a horse-drawn
drill around 1701. He promoted sowing seeds in rows rather than broadcasting
(simply casting the seeds around), so that weeds could be controlled by
hoeing regularly between the rows. For this purpose, he devised his seed
drill, which could planted three rows at the same time. A blade cut a groove
in the ground to receive the seed, and the soil was turned over to cover
the sewn seed. A hopper distributed a regulated amount of seed. Because
of the internal moving parts, it has been called the first agricultural
machinery. Its rotary mechanism became part of all sowing devices that followed.
Tull also invented a four-coultered plow to make vertical cuts in the soil
before the plowshare.