 The first case involves the Golgi apparatus, first described by Golgi (1898) in light microscope studies using the silver nitrate stain he had introduced. Palade and Claude (1949a,b), two of the pioneers of modern cell biology, who would ultimately share the Nobel Prize, argued that it was an artifact of staining, including with osmium tetroxide (which Palade helped establish as a primary stain for electron microscopy). They appealed not only to the variable appearance of the Golgi bodies, as had some earlier skeptics (Strangeways &amp; Canti 1927; Parat 1928; Baker 1944), but also to their own ability to create myelin figures similar in appearance to the Golgi bodies by adding osmium to egg white. As discussed by Bechtel (2006), this is compelling evidence for the claim that the Golgi apparatus is an artifact, but in this case the evidence was eventually set aside without being refuted. Although Palade remained a skeptic about the Golgi apparatus for 15 years (researchers in his lab reported that they were not allowed to mention it during that interval), he finally accepted its reality when researchers in his laboratory demonstrated that many newly synthesized proteins pass through the region of the cell where the Golgi apparatus appeared on their way to being secreted. He did not, however, explain why he changed his mind. This later research on the Golgi apparatus, but not his earlier skepticism about the existence of the Golgi apparatus, was noted in Palade’s Nobel Prize citation in 1974. Palade himself later contributed to two reviews (Farquhar &amp; Palade 1981, 1998) that discuss earlier researchers who cast doubts on the reality of the Golgi apparatus, but he never mentions his own claims that it was an artifact. What seems particularly salient is that, as a result of research in his laboratory, the Golgi apparatus was associated with a function in the cell in a manner that it had not been previously. It now fit into a plausible theory in which it figured in packaging proteins for export from the cell. Bechtel argues that this is often a major factor in researchers’ acceptance of the reality of entities identified through new techniques.