As promised, the little article I read about beri-beri.
Leaving in the note that follows just because how could I not.
Beri-beri is actually caused by a vitamin deficiency. It really is connected with rice, just not in the way the author of this piece thinks: a diet of polished and unfortified white rice doesn't supply enough vitamin B1. Presumably the disappearance of beri-beri among the medical students is explained by the change in diet when they began boarding with others instead of dining on the communal rice.
You see similar situations over and over in discussions of beri-beri from this era. The facts, meticulously described (more in other accounts than in this one), and clearly explainable once you know the actual cause of the disease, but at the time attributed very plausibly to some kind of taint or parasite in the white rice itself. I wouldn't have imagined how closely a deficiency in a staple food can resemble a contamination.
Still need to figure out what this "breeding pearls" business is all about.
