Henri Hallopeau (Fig. 1, Fig. 2) was born in Paris on 17th January 1842, the son of François Hallopeau (1811–1879), “lieutenant principal des douanes” (customs officer), and Adélaïde Rossignol (1810–1886), from the Belgian city of Ostend [1]. After brilliant secondary studies at the prestigious Lycée Bonaparte (later named Lycée Condorcet), Hallopeau, who in 1857 ranked first on the competitive exam marking the end of his secondary education, enrolled in the Paris Medical School in 1858. After