If you believe the interpretation placed by Bias Cabrera of Stanford University on the stepped increase of the current circulation in his superconducting ring device recorded a few months ago, you believe that a magnetic monopole has been observed (Phys. Rev. Lett., 48, 1378, 1982). Certain natural events can be considered statistically reliable observationally if they are demonstrated to occur only once. Cabrera set u p the experiment carefully; he could be right. The results have triggered around of theoretical entertainment, the calculations being aimed at analysing the consequences of the deduced ‘flux’ of monopoles sampled by Cabrera's experiment.