The publication of Cantor’s ‘Beitrag’ (‘Contribution’) towards the beginning of 1878 immediately caused a flurry of mathematical activity. The objective at this point was to save the concept of dimension. The counterintuitive correspondence between geometrical objects of different dimensions had to be explained. During the months July to October 1878, when Cantor’s paper had barely left the presses, five mathematicians attempted to demonstrate the invariance of dimension through a consideration of continuity—just as Dedekind had suggested in his letters to Cantor.