Historians of Victorian Britain still know surprisingly little about the lives of London's poor. The decennial censuses confirmed a substantial and sustained growth in raw numbers: the overall population of the capital increased by almost 150 per cent between 1801 and 1851. Most working people endured perilously mobile lives as they chased new, and usually short-term, opportunities for unskilled labour either on the docks or on new buildings in the City. Regular, adequately remunerated employment was, by contrast, the preserve of a skilled elite. ‘Midnight flights’ were another feature of lower working-class life as families tried to escape the practised clutches of the rent-collector. Why, then, the knowledge deficit? The most obvious reason was the lack of literacy among the poorest. For most, knowledge and understanding had to be communicated verbally, with all the attendant difficulties in the way of ‘deep learning’ and ‘bedding down’. As Donald Lewis argues persuasively in this well-organised work, the lack of sustained middle-class engagement with working-class culture was a major reason for mutual misunderstandings between the classes and especially so in matters of faith where Evangelicalism was dominant. The London City Mission's key instruction to its missionaries when visiting working-class families was to bring them to ‘an acquaintance with salvation through our Lord Jesus Christ, and of doing them good by every means in your power’. The emphasis was on improving the religious knowledge and understanding of the poor and on making converts. What the poor's understanding of the Evangelical agenda might be seems to have been varied but limited. Lewis's new book complements his Lighten their darkness (Oxford 1986), a study of how the City Mission communicated with the poor. The present work is anchored in one source, a manuscript journal written by Joseph Oppenheimer, an Evangelical missionary from a Jewish family. Lewis claims that it ‘appears to be the only surviving manuscript journal of its kind from the nineteenth century’. Debates on definitional categorisation aside, the journal offers indicative examples of the response of the poor to the moral assault of the missionaries. Oppenheimer notes numerous examples of gratitude shown by the poor for the visits that they received. However, he seems to have had particular trouble in his visits to Roman Catholic households. His manuscript reported that a ‘very bigoted’ Catholic ‘named Riley told me to go to the Devil or he would knock my brains out if I did not leave his house at once’. A woman with five children and almost no income told Oppenheimer that ‘I wish we were all dead … we could not be worse off than we are now… I don't believe that there is a God at all, if there is He don't much care for us.’ Lewis has unearthed, and made effective use of, a neglected source. Readers should not expect to encounter a second Mayhew here. Oppenheimer was not a stylist and his range is much is narrower. Nevertheless, in rescuing him from obscurity, Lewis has made a significant contribution to our understanding of Victorian Evangelicalism.