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The image shows the electron micrograph of the endothelium of a small pulmonary artery of a rat recorded by Ewald R.Weibel on February 14, 1962, while working with George E. Palade (1914-2009) at The Rockefeller Institute in New York. On the screen of the electron microscope Weibel had noted large bodies in the cytoplasm and recorded this micrograph out of curiosity, even though the section looked dirty and scratched. When examining an enlarged print he realized that the “stick” in the top left quadrant was not a “dust particle,” as originally presumed, but a constituent of the endothelial cytoplasm. The probability of cutting a long, thin, rod-shaped particle longitudinally from one end to the other is extremely low; most sections would cut across and yield round or elliptic profiles. Several such profiles are seen in the immediate neighborhood of the rod, and dozens in the entire picture. What would later be called “Weibel-Palade bodies” were born—a great case of serendipity. See Weibel ER, Palade GE. New cytoplasmic components in arterial endothelia. J Cell Biol. 1964;23:101–112.