Adam Edwards

We propose a new account of calibration according to which calibrating a technique shows that the technique does what it is supposed to do. To motivate our account, we examine an early twentieth-century debate about chlorophyll chemistry and Mikhail Tswett’s use of chromatographic adsorption analysis to study it. We argue that Tswett’s experiments established that his technique was reliable in the special case of chlorophyll without relying on either a theory or a standard calibration experiment. We suggest that Tswett broke the experimenters’ regress by appealing to material facts in the common ground for chemists at the time.

During the course of this article, we examine the use of membership categorisation practices by a high-profile celebrity public social media account that has been understood to generate interest, attention and controversy across the UK media ecology. We utilise a data set of harvested tweets gathered from a high-profile public ‘celebrity antagonist’ in order to systematically identify types of antagonistic formulation that have generated different levels of interest within the social media community and beyond. Drawing from classic ethnomethodological studies of banner headlines and other means of generating public interest and ‘making sense’, we respecify high-profile antagonistic tweets as category formulations that exhibit particular and regular membership category features that are reflexively bound to potential antagonistic readings, interest and controversy. In conclusion, we consider how such formulations may be understood to represent resources that constitute ignition points within antagonistic flows of communication and information that can be metaphorically understood as ‘digital wildfires’.