I am grateful to John Springhall for his kind and constructive comments, and in response would like to briefly flag up a few areas that have occurred to me as worthy of further consideration and development.
Firstly, the regional angle. It seems to me that there is an issue of regional/geographic spatiality that needs to be considered in studying juvenile crime in the nineteenth century. Many European countries were undergoing periods of innovation in the punishment and welfare of the young delinquent during the period in question. The most well known examples of institutional development I mention in the book, Mettray in France, and the Rauhe Haus in Germany. However, current research by European historians has shown similar broad patterns in a number of (particularly northern) European countries which are worth further investigation. On a more local level, patterns of difference in England/Britain need to be further considered. Peter King has started to do this in his research, comparing the Middlesex records with the Home Circuits records, and Assize records (Bristol, Shropshire, Lancashire, Gloucestershire). However, there is certainly room for further investigation, for example of rural/urban difference, and of the impact of the big industrialising areas of the north.
Another issue is that of gender. The discourse of juvenile crime in the early nineteenth century is strongly underpinned by traditional notions of gender, which in turn impact on the systems of reform which were a feature of the institutional experience for young offenders. I do discuss this briefly in the book (particularly pp. 9-11, 97-8) and elsewhere (see essay, 'The Trouble with Boys: Gender and the 'Invention' of the Juvenile Offender in the Early Nineteenth Century', in M. Arnot & C. Usborne (eds), Gender and Crime in Modern Europe (UCL Press, 1999)). However, much of the discussion of gender, and particularly of girl delinquency, has been located in the context of the reformatories and industrial schools, for example in work by Pamela Cox, Michelle Cale, and Linda Mahood, and hence has largely concentrated on the later nineteenth century, and early twentieth. Whilst this institutional bias is an inevitable product of the available source material, I would argue strongly for further research in this area. A relationship that so preoccupies modern commentators, is that between media and crime, and certainly the reporting of juvenile crime in the nineteenth century media could be developed. Andrew Davies has undertaken some work of this nature on street youth/gangs in his work on the Salford Scuttlers, however this is a comparatively under researched area.
A final theme for further consideration, which again I have dealt with in the book albeit indirectly, is the issue of language. It seems to me, that if historians of juvenile crime and delinquent youth are going to move away from continual discussions of chronology, and 'invention', we need to do more work on the shifts in public and elite perceptions of crime, and particularly juvenile crime, that occur in this period. A fluid model of language, I would argue, is central to understanding the development in both perceptions, and legal re-conceptions of juvenile crime, but also crime more generally.