The Story of KIPPON: How a Nuclear Physicist Solved the Age-Old Kippah Dilemma
Part I: A Problem as Old as the Kippah Itself
From the essay
Enter Rabbi Sholom Ber Schapiro, a Brooklyn-based Hasidic scholar with a sharp mind and a keen eye for practical problems. One day, while teaching Chassidic philosophy, he noticed a student sitting bareheaded. When questioned, the young man simply replied that he had lost the bobby pin that held his kippah in place. Concerned that such a minor inconvenience might lead someone to forgo wearing a yarmulke altogether, Rabbi Schapiro decided to act.
Adapted from PDF pages 1.