Schmidt studied with Rose and Müller in Berlin before becoming one of Liebig’s research students. He then worked for a year with Wöhler. The older Bidder was Schmidt’s great collaborator; although they didn’t work together again after publication of their great double study of digestion and metabolism, they remained university colleagues and good friends.
Strecker was the first person to synthesise an amino acid (alanine). He studied under Liebig, then returned as his assistant, teaching Kekulé (among others) organic chemistry. Meyer, working under Liebig at the same time, became a good friend. Miescher (who importantly went on to isolate the DNA molecule) worked as a research student under his guidance. Strecker is credited as co-author of the German edition of Regnault’s influential chemistry text-book; while both were graduates of Liebig’s laboratory, it is unclear what contact the two had.
Regnault made extensive contributions to 19th-century chemistry (he was the first to synthesise PVC, albeit accidentally) and physics (showing Boyle’s law to be only approximate), as well as contributing to the development of photography. He worked under Liebig, and was Gay-Lussac’s demonstrator at the École Polytechnique. He collaborated with Foucault on research into binocular vision, was a colleague of Biot’s, and wrote a comprehensive chemistry textbook, influential in both its French and German editions. Bunsen, Herschel and Airy were correspondents.
Vauquelin worked as Fourcroy’s assistant for eight years, becoming his close friend and collaborator: they published over fifty joint research papers. He also collaborated with Brongniart, and succeeded him as professor of chemistry at the Jardin des Plantes. He taught Thénard, Chevreul and Stromeyer, Thénard coming to him (impoverished, of peasant origins) just as he had gone to Fourcroy. Berthollet, Lavoisier and Gay-Lussac were all friends. Fourcroy and Haüy advised him on the naming of chromium (because of its colourful compounds). He protected his student Orfila, the founder of toxicology, during the Peninsular War.
Chaptal’s development of industrial chemistry in France lies at the heart of a much broader programme of influential progressive reforms. He was a senior member of Berthollet and Laplace’s Société d’Arcueil, and succeeded Berthollet at the École Polytechnique. He appointed Vauquelin as director of the school of pharmacy, provoked Thénard’s development of cobalt blue pigment, and was among those Carnot worked with to get enlightened technical policies enacted. Berthollet, Monge and Laplace were particularly close friends, visiting him at the château he restored where he produced beet sugar and eau-de-vie.
Courtois discovered iodine, which, medical importance aside, made early photography possible, and jointly discovered morphine. He grew up around Guyton de Morveau’s Dijon academy — his father worked there, the family lived there. Thénard, the same age, became a good friend when both got jobs under Fourcroy in Paris. Helping another researcher there, Séguin, Courtois isolated morphine (Séguin tried to claim all the credit). Too preoccupied with business to research further, Courtois gave samples of iodine to his friends Clément and Desormes, who passed it on to Ampère, Chaptal, Gay-Lussac and ultimately Davy.
It is an over-simplification to think of Nobel only in terms of explosives, much as they overshadow his patents for such things as artificial silk and leather. Zinin was engaged by Nobel’s father Immanuel as a private tutor when the family lived in Russia. Nobel later worked in Pelouze’s laboratory for a year. Zinin reminded him of the disconcerting discovery of another of Pelouze’s students, Ascanio Sobrero: nitroglycerine. Nobel managed to stabilise it, and commercially exploited it as well as other discoveries of his own, e.g. gelignite. Hugo, perhaps an unlikely friend, called Nobel the richest vagabond in the world.
As a student, Guyton met Voltaire, who later praised a parliamentary speech of his. Hachette accompanied him into battle (during which Guyton took to the air in a balloon), while Buffon encouraged his interest in science. Initially unpersuaded by Lavoisier’s ideas, he was then won over; Lavoisier, Berthollet and Fourcroy joined him in getting his ideas about a rational nomenclature for chemistry established. Monge and Carnot were founder-colleagues at the École Polytechnique, and Gay-Lussac a student. Bergman was a long-term correspondent, Young was very impressed by his lab, but Davy described him as old and feeble.
He was Berthollet’s teaching assistant and Fourcroy’s demonstrator. Laplace encouraged him; he worked on potassium and sodium with Thénard. He criticised Humboldt for a lack of precision, but they became friends and travelled together, climbed Vesuvius in full eruption, and showed that the composition of air does not change with altitude. Liebig, Pelouze and Regnault were all students of his. Biot and he made the first balloon ascent for scientific study; on another balloon flight he threw a chair overboard to gain height, causing locals to marvel that God owned such shabby furniture.
Duclaux worked as an assistant to Pasteur for a few years, later returning as a senior collaborator before succeeding him as director of the Pasteur Institute, with Roux and Chamberland as close colleagues. He worked closely with Pasteur on sikworm disease and the fermentation of beer, and joined him in the debate about spontaneous generation. While based outside the Pasteur Institute (he held a succession of academic appointments), he remained a close associate of Pasteur’s. Perrin was a correspondent, and a fellow-leader of the defenders of Captain Dreyfus in a notorious case of institutional anti-semitism.