Dundas's main task was to frustrate any possibility that Napoleon might exploit his alliance with Russia to make some attempt on British India.

He ordered the occupation of the Portuguese factories in India and China, of the Dutch colony of Java, and of the French stations on Mauritius and Réunion.

Spencer Perceval, succeeding Portland, then wanted to promote him to the cabinet as secretary for war, but this did not happen due to the wishes of his father.

In a state paper of February 1813 he pointed out that France, with the shipbuilding resources of the Netherlands and Italy at her disposal, would be able to construct a fleet to match Britain's if the struggle continued much longer.

The point was underlined by complaints from the Duke of Wellington in Spain of inadequate protection for the convoys supplying him, especially after the outbreak of hostilities with the United States in 1812 unleashed hordes of American privateers on the Atlantic.

Drastic cuts followed the eventual peace, but Britain, now the only colonial power of any importance, found her maritime commitments increased.

The following years saw a constant struggle by Melville to find every possible economy while he avoided meeting a target he regarded as unreal.

Yet he resisted the introduction of steamers, since an infant technology seemed bound to prove expensive and unreliable; moreover, if navies were to be rebuilt all round as steam driven, Britain would place herself on the same level as her rivals.

Appointed a governor of the Bank of Scotland, he was elected chancellor of the University of St Andrews in 1814, and made a Knight of the Thistle in 1821.

The Whigs in Canning's coalition now persuaded him that a Scottish manager was unnecessary; the home secretary could do all the work with a native adviser or two.

But he made himself useful in good works, notably chairmanship of the royal commission which in 1845 proposed reform of the Scots poor law.