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At the dawn of history we find man practicing the most elementary methods of modifying soil conditions. He broke up the surface and prepared a seed-bed, using for this purpose the most primitive of all cultivating devices, a digging implement like a hoe. In early times the principal crops were cereals and flax.
By the 19th century such a complexity of implements had been introduced as to justify the term «agricultural machinery». In agriculture, as in industry, the use first of water-power and then of steam had immensely stimulated the invention of machinery or replacing manual labour. A threshing-machine was invested late in the 18th century and was gradually coming into use early in the 19th. It was driven by water or wind, sometimes by horse labour and later by steam. The mowing-machine, the self-binder and the potato-digger had been developed in the first instance for horse or manual labour.
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What stimulated the invention of machinery?
The use of a threshing-machine did.
The use of the mowing-machine, the self-binder and the potato-digger did.
The use of a digging implement did.
The use of water-power and of steam did.