Two Nature papers published 100 years apart on the role of tension in brain cortex folding are connected by a historical footnote.

I discovered this as a result of a coincidence: the brain of the poet Walt Whitman and that of anatomist Andrew Parker ended up in a lab waste bin after dying within a week of one another in 1892. Both had been collected by the secretive American Anthropometric Society, which sought to uncover neuroanatomical features in the brains of eminent people. Unfortunately, Whitman's brain shattered after being dropped on the floor; Parker's crumbled after soaking in fixative for too long.

Beyond this shared fate of neural machinery, there is little information about Parker himself. My investigations revealed that he had proposed a mathematical theory of cortical folding based on the laws of liquid films and surface tension (see W. B. Benham Nature 55, 619–620; 1897) — ironic, considering that the laws of liquid physics and chemical reactions crumbled his brain. I also found that his conclusions nicely complement a theory put forward a century later (D. C. Van Essen Nature 385, 313–318; 1997).