resulted in an agricultural revolution in the province, rapid industrial growth, and the resettlement of over one million Punjabis in the new areas. A number of towns were created or saw significant development in the colonies, such as Lyallpur, Sargodha and Montgomery. Colonisation led to the canal irrigated area of the Punjab increasing from three to fourteen million acres in the period from 1885 to 1947. The beginning of the twentieth century saw increasing unrest in the Punjab. Conditions in the Chenab colony, together with land reforms such as the Punjab Land Alienation Act, 1900 and the Colonisation Bill, 1906 contributed to the 1907 Punjab unrest. The unrest was unlike any previous agitation in the province as the government had for the first time aggrieved a large portion of the rural population. Mass demonstrations were organised, headed by Lala Lajpat Rai, a leader of the Hindu revivalist sect Arya Samaj. The unrest resulted in the repeal of the Colonisation Bill and the end of paternalist policies in the colonies. During the First World War, Punjabi manpower contributed heavily to the Indian Army. Out of a total of 683,149 combat troops, 349,688 hailed from the province. In 1918, an influenza epidemic broke out in the province, resulting in the deaths of an estimated 962,937 people or 4.77 percent of the total estimated population. In March 1919 the Rowlatt Act was passed extending emergency measures of detention and incarceration in response to the perceived threat of terrorism from revolutionary nationalist organisations. This led to the infamous Jallianwala Bagh massacre in April 1919, where Colonel Reginald Edward Harry Dyer ordered detachments of the 9th Gorkha Rifles and the 59th Scinde Rifles under his command to fire into a group of some 10,000 unarmed protesters and Baisakhi pilgrims, killing 379. Administrative reforms The Montagu–Chelmsford Reforms enacted through the Government of India Act 1919 expanded the Punjab Legislative Council and introduced the principle of dyarchy, whereby certain responsibilities such as agriculture, health, education, and local government, were transferred to elected ministers. The first Punjab Legislative Council under the 1919 Act was constituted in 1921, comprising 93 members, seventy per cent to be elected and rest to be nominated. Some of the British Indian ministers under the dyarchy scheme were Sir Sheikh Abdul Qadir, Sir Shahab-ud-Din Virk and Lala Hari Kishen Lal. The Government of India Act 1935 introduced provincial autonomy to Punjab replacing the system