108 ESSAYS BIOGRAPHICAL AND CHEMICAL 



was a national fete. Thus did the French honour science 

 and its doyen. 



On March 18, 1907, the end came. Madame Berthelot 

 had been ailing for about three months ; it turned out to 

 be an attack of heart-disease, dangerous at the age of 

 seventy. After she was confined to bed, Berthelot watched 

 by her each night, seated in a deep arm-chair, only leaving 

 her when she was asleep. He himself suffered from the 

 same disease, and it was accelerated by his want of rest. 

 His family noticed his feverish appearance in the morn- 

 ings ; he excused himself by saying that he was finishing 

 a memoir for publication. On Passion Sunday there was 

 a slight improvement, and Berthelot passed the afternoon 

 in his laboratory at Meudon. That night, however, 

 Madame Berthelot became comatose, and her husband 

 never left her bedside until Monday at four, when the end 

 came. Berthelot suddenly rose from the arm-chair in 

 which he was seated, threw his arms in the air, uttered a 

 cry, and fell back dead. They died, as they had lived, 

 together. 



It now remains to give a sketch of Berthelot's scientific 

 work. The ' Prix- Jecker ' has already been alluded to. 

 This was the reward of his labours on the synthesis of 

 carbon compounds. He began in 1851 by investigating 

 the action of a red-heat on alcohol, acetic acid, naphtha- 

 lene, and benzene ; this led him in 1860 to the rediscovery 

 of acetylene, a compound originally obtained by Edmund 

 Davy, Sir Humphry's brother. In 1856 he synthesised 

 methane by the action of a mixture of sulphuretted 

 hydrogen with carbon disulphide on copper ; and in 1862 

 he obtained ethylene and acetylene by heating marsh-gas 

 to redness. His condensation of acetylene to benzene in 

 1866 established the first link between the fatty and the 

 aromatic series. His direct synthesis of acetylene from 

 carbon and hydrogen in 1862, and the formation of alcohol 



