This paper explores how, at the 1875 Royal Commission on Vivisection, the anaesthetised animal was construed as a boundary object around which “cooperation without consensus” Computer supported cooperative work: cooperation or conflict? Springer, London, 1993) could form, serving the interests of both scientists and animals. Advocates of anaesthesia presented it as benevolently intervening between the scientific agent and animal patient. Such articulations of ‘ethical’ vivisection through anaesthesia were then mandated in the 1876 Cruelty to Animals Act, and thus have had (...) significant downstream effects on the regulation of laboratory animals in Britain and beyond. Constructing this ‘consensus’ around the anaesthetised animal, however, required first excluding abolitionists and inhumane scientists, and secondly limiting the interests of experimental animals to the avoidance of pain through anaesthesia and euthanasia, thereby circumventing the issue of their possible interest in future life. This consensus also served to secure the interests of vivisecting scientists and to limit the influence of public opinion in the laboratory to administrative procedure and scheduled inspection. The focus on anaesthesia was connected with discussions of what supporting infrastructures were required to ensure proper ethical procedure was carried out by scientists. In contrast to the much studied polarisation in British society between pro- and antivivisectionists after 1876, we understand the 1875 Commission as a conflict amongst scientists themselves, while also being an intra-class conflict amongst the ruling class. (shrink)