What were the factors for the introduction of threshing machines during the Napoleonic Wars? What were its effect after the Napoleonic wars in England?

(a) The factors for the introduction of threshing machines were as given below:
(i) Expansion of production by the farmers due to high prices of foodgrains.
(ii) Fear of shortage of labour.
(ii) Complaints of insolence of labourers, their drinking habits, and the difficulty of making them work
(v) To reduce their dependence on labourers.
(b) After the Napoleonic wars, thousands of soldiers returned to their homes. They
needed jobs but there was no work due to reduction in the cultivation area and use of threshing machines. This led to riots.