Berthelot’s bomb calorimeter

The famous love stories of chemistry always end in tragedy, don’t they? Marie Anne Paulze’s marriage to Antoine-Laurent Lavoisier redefined chemistry. But it ended when Lavoisier was guillotined. Pierre and Marie Curie’s laboratory love tryst led them to the Nobel Prize. But it ended abruptly when Pierre was killed in a road accident.

Our romantic hopes can be restored by the story of Marcellin Berthelot and Sophie Niaudet, whose love lasted for decades; each was the pivot around which the life of the other revolved. Berthelot was the son of a doctor who worked among the poor of central Paris in the decades after Napoleon was finally consigned to the arsenic-saturated outpost of St Helena. The young Marcellin, who grew up a sickly child, saw the poverty for himself, and had an extremely strong sense of the precarity of life – this sense of insecurity may have been part of the driving force of his life.

His parents sent him to the legendary Collège Henri IV. He was a quiet, brilliant student, excelling in classics and philosophy. A few years later one of the teachers, Ernest Renan, only four years his senior, later a distinguished historian and essayist, was assigned a room beside Berthelot’s. Their conversations became a profound life-long friendship and probably helped cement Berthelot’s rejection of his Catholic upbringing; it also led to Berthelot rejecting the Grandes Écoles, and to become a scientist. He ended up studying at the Sorbonne with Antoine-Jérôme Balard, the discoverer of bromine. Berthelot became Balard’s assistant and his thesis concerned the synthesis of fats from glycerine and fatty acids. He successfully made the mono-, di- and triglycerides, a major advance at the time. But he remained stuck in temporary positions and was supported by his parents until the age of 30.