Accanto alla rivoluzione industriale un altro fenomeno ha segnato il passaggio dal mondo moderno al mondo contemporaneo: la rivoluzione agricola, che ha portato all’utilizzo di nuove tecniche di coltivazione, come la rotazione delle colture,  e di nuovi strumenti agricoli. Uno dei fattori che più ha inciso nel cambiare l’agricoltura,  secondo Carl Seaver in un articolo pubblicato su History defined, fu la quantità di cibo che un lavoratore poteva produrre in Inghilterra grazie alla seminatrice di Jethro Tull (1674-1741).

Carl Seaver racconta come nella storia umana i semi siano stati sempre seminati manualmente, preparando il terreno prima della semina e spargendoli in gran quantità lanciandoli sul terreno.

The idea was that, while many seeds would not take root, such as the volume scattered, some inevitably would, and these would emerge as crops come to the harvest. In practice, this was as wasteful and unscientific as it sounds, and it is incredible that it would take until the eighteenth century for a more effective method to emerge. However, primitive seed drills had been used in ancient Sumer and China thousands of years earlier.

Le antiche seminatrici sumere e cinesi non furono mai utilizzate in Europa e il lavoro manuale continuò fino all’invenzione di Jethro Tull, un avvocato ammalato ai polmoni che trascorse la sua convalescenza in Francia dove potè studiare le tecniche agricole.

Tull is believed to have invented his first seed drill in 1701. Further innovations and tweaks over the next three decades resulted in the full Tull seed drill by the early 1730s.

Questa invenzione secondo l’autore migliorò in modo consistente le rese agricole.

Carl Seaver narra come la produttività nell’agricoltura europea aumentò e l’Europa si ritrovò con un surplus di cibo che consentì l’espandersi della popolazione e una diminuzione delle malattie dovute alla malnutrizione. L’agricoltura liberò molti lavoratori grazie a questa invenzione che vennero occupati nelle fabbriche  e parteciparono alla rivoluzione industriale.

Il  ruolo di Jethro Tull è stato davvero così importante o fu solo uno dei tanti fattori che portarono al cambiamento?  Su Science Direct un lavoro di Laura B. Sayre approfondiva il tema in un articolo intitolato “La preistoria della scienza del suolo: Jethro Tull, l’invenzione della seminatrice e le basi dell’agricoltura moderna”:

Abstract: Eighteenth-century British gentleman farmer Jethro Tull (1674–1741) is popularly regarded as the inventor of the seed drill, widely cited by agricultural historians, soil scientists and school history textbooks alike. Whether Tull was in fact the first to experiment with a mechanical seed drill and the horse-drawn cultivators drilling made possible is doubtful, but he did do much to make their acceptance in the long run more widespread. What is less well known is that Tull’s mechanical innovations were accompanied by a theory of plant nutrition—and a social agenda—that were equally important to the adoption of the new machines. Although he came to be celebrated by later generations, Tull’s work attracted fierce critics in his own day and immediately after, not least because he categorically rejected the value of manures in maintaining soil fertility. Instead, he proposed a mechanistic theory of plant nutrition in which the stirring of the soil with the cultivator could substitute for the processes of decomposition thought to be contributed by manures, with less labor and expense. For Tull, the drill was part of an explicit strategy to minimize reliance on an unruly labor force. He also directly challenged the idea that Virgil and other classical authorities could be of any practical use in farm management. In other words, Tull was an anti-georgic improver, and could only be reinserted into the canon of agricultural history through the efforts of later agriculturists to gloss over the objectionable parts of his work. This paper explores how, a century before Liebig, Tull’s Horse-Hoeing Husbandry (1731 and later editions) sparked heated debates over a constellation of issues that are still with us today: no-till vs. tillage, net profits vs. gross yields, soil biology vs. soil chemistry, yield per acre vs. yield per unit of labor, rotation costs vs. input costs.

Ne parlava anche sulla BBC il professor Mark Overton in un articolo intitolato Agricultural Revolution in England 1500 – 1850.

For many years the agricultural revolution in England was thought to have occurred because of three major changes: the selective breeding of livestock; the removal of common property rights to land; and new systems of cropping, involving turnips and clover. All this was thought to have been due to a group of heroic individuals, who, according to one account, are ‘a band of men whose names are, or ought to be, household words with English farmers: Jethro Tull, Lord Townshend, Arthur Young, Bakewell, Coke of Holkham and the Collings.’ These men are seen as having triumphed over a conservative mass of country bumpkins. They are thought to have single-handedly, in a few years, transformed English agriculture from a peasant subsistence economy to a thriving capitalist agricultural system, capable of feeding the teeming millions in the new industrial cities. All these details are in some dispute, but there is general agreement that the role of the ‘Great Men’ as pioneers and innovators has been exaggerated.