 Mayo gives an additional example of how a use-constructed hypothesis can count as having survived a severe test that pertains to the famous 1919 Eddington eclipse experiment of Einstein’s General Theory of Relativity. GTR predicted that starlight that passed by the sun would be bent to a specific degree (specifically 1.75 arcseconds). There were actually two expeditions carried out during the eclipse—one to Sobral in Northern Brazil and the other to the island of Principe in the Gulf of Guinea. Each expedition generated a result that supported GTR, but there was a third result generated by the Sobral expedition that appeared to refute GTR. This result was however disqualified because it was determined that a mirror used to acquire the images of the stars’ position had been damaged by the heat of the sun. While one might worry that such dismissing of anomalous evidence was the kind of ad hoc adjustment that Popper warned against, Mayo notes that this is instead a perfectly legitimate case of using evidence to support a hypothesis (that the third result was unreliable) that amounted to that hypothesis having passed a severe test. Mayo concludes that a general prohibition on use-constructed hypothesis “fails to distinguish between problematic and unproblematic use-constructions (or double countings)” (1996: 285). However, Hudson (2003) argues that there is historical evidence that suggests there was legitimate reason to question the hypothesis that the third result was unreliable (he uses this point to support his own contention that the fact that a hypothesis was use-constructed is prima facie evidence that the hypothesis is suspect). Mayo (2003) replies that insofar as the third result was nonetheless suspect the physicists involved were right to discard it. 