Chalmers then opened mathematical classes on his own account which attracted many students; at the same time he delivered a course of lectures on chemistry, and ministered to his parish at Kilmany.

[5] In 1815 he became minister of the Tron Church, Glasgow, in spite of determined opposition to him in the town council on the grounds of his evangelical teaching.

[9] In November 1817 Chalmers used a memorial sermon for Princess Charlotte of Wales to appeal for a Christian effort to deal with the social condition of Glasgow.

He declared that twenty new churches, with parishes, should be erected in Glasgow; and he set to work to revive the old parochial economy of Scotland.

[10] In 1823 Chalmers accepted the chair of moral philosophy at the University of St Andrews, the seventh academic offer made to him during his eight years in Glasgow.

[10] In 1834 Chalmers was elected fellow of the Royal Society of Edinburgh, and in the same year he became corresponding member of the Institute of France; in 1835 Oxford conferred on him the degree of DCL.

He was appointed chairman of a committee for church extension, and in that capacity made a tour through a large part of Scotland, addressing presbyteries and holding public meetings.

[15] Chalmers found himself at the head of the party in the Church of Scotland which stood for "non-intrusionism": the principle that no minister should be intruded into any parish contrary to the will of the congregation.

The non-intrusionist movement ended in the Disruption: on 18 May 1843, 470 clergy withdrew from the general assembly and constituted themselves the Free Church of Scotland, with Chalmers as moderator.

"[19] On 28 May 1847 Chalmers returned to his house at Church Hill[20] in Morningside, near Edinburgh, from a journey to London on the subject of national education.

On Sunday, the 30th, he continued in his usual health and spirits, and retired to rest with the intention of rising at an early hour to finish his report.

A series of sermons on the relation between the discoveries of astronomy and the Christian revelation was published in January 1817, and within a year nine editions and 20,000 copies were in circulation.

[5] In 1808 Chalmers published an Inquiry into the Extent and Stability of National Resources, a contribution to the discussion created by Bonaparte's commercial policy.

He was the first also to advance that argument in favour of religious establishments which met on its own ground the doctrine of Adam Smith, that religion—like other things—should be left to the operation of the law of supply and demand.

[26] In 1826 he published a third volume of The Christian and Civic Economy of Large Towns, a continuation of work begun at St John's, Glasgow.

[31] In arguing that private charity should outweigh public expenditure in relieving poverty, he was one of a group of British writers of the period of similar views, that included also Samuel Richard Bosanquet, Thomas Mozley and Frederick Oakeley.

[33] In his St Andrews lectures Chalmers excluded mental philosophy and included the whole sphere of moral obligation, dealing with man's duty to God and to his fellow-men in the light of Christian teaching.

[10] In the field of ethics he made contributions in regard to the place and functions of volition and attention, the separate and underived character of the moral sentiments, and the distinction between the virtues of perfect and imperfect obligation.

The separate publication of this article, and contributions to the Edinburgh Christian Instructor and The Eclectic Review, enhanced his reputation as an author.

"[10] Chalmers' Bridgewater Treatise, in the series On the Power, Wisdom and Goodness of God as Manifested in the Adaptation of External Nature to the Moral and Intellectual Constitution of Man, appeared in two volumes 1833 and went through 6 editions.

[34] As noted by Robert M. Young, these books effectively represent an encyclopedia of pre-evolutionary natural history, commissioned and published whilst Charles Darwin was on board the Beagle.

In the area of natural theology and the Christian evidences he advocated the method of reconciling the Mosaic narrative with the indefinite antiquity of the globe which William Buckland advanced in his Bridgewater Treatises, and which Chalmers had previously communicated to him.

He wrote of Genesis 1:1: "My own opinion, as published in 1814, is that it forms no part of the first day but refers to a period of indefinite antiquity when God created the worlds out of nothing.