When John Davies, who combined employment at the Rolls Chapel Office with a patent agent's practice, published his treatise on patent law in 1816, he commented on the spectacular growth of business he had witnessed over the preceding thirty years.

Davies's example notwithstanding, I shall now draw together points made in the previous three chapters in an attempt to explain the late-eighteenth-century rise in the patent totals. Fifty years before Davies wrote, the annual figures had started their exponential climb: in 1766 the unprecedented total of 31 had been reached; in 1816 Davies and his colleagues dealt with 118 patents.

It can never be disproved that the positivist explanation of the rise patents – an upsurge in inventive activity or of new found technical talent – is incorrect. The list of well-known inventions that date from the later eighteenth century suggests that it certainly contains some degree of truth (though partly at the expense of the Saverys, Newcomens, Wyatts and Pauls of the century's first half). But to ask why it should have occurred then and in England is to enter anything but a positivist realm: from the impact of the scientific revolution to explanations couched in terms of socio-psychology, historians continue to speculate, while some take refuge in the ‘randomness’ of invention's timing.