This chapter discusses some points in relation to the Bolton/Worktown Corpus (BWC) and the Mayhew Corpus (MC) namely: chance discovery of the data, the historical background to the data, the nature and verisimilitude of the data and the compilation process. As the process of discovering and collecting the data is important to an assessment of its value, a short anecdotal interlude is unavoidable. There is, unfortunately, no detailed account of how the observers went about the task of transcribing spoken data or whether/how they were trained to do it. The process of compiling the MC simply involved identifying and extracting the interview data which is embedded in London Labour and the London Poor (LLLP) in background commentary and statistical analysis of social issues. As with the BWC, serendipity, curiosity and perseverance were important in the genesis of the MC. The chapter concludes with some general reflections on the process of authenticating the data in the BWC and the MC.