The fourth volume of Thomas Pinney's acclaimed edition of Macaulay's letters covers the period between September 1841 and December 1848, in which Macaulay is shown keeping up an active political life as MP for Edinburgh and member of Lord John Russell's Whig Cabinet. At the same time his literary reputation is extended by The Lays of Ancient Rome, the collected Essays, and, at the end of the period spanned by this volume, the triumphant publication...