Eugène CHEVREUL (1786-1889). L.A.S., Paris, March 212, 1871, to his "honored colleague" [Ludovic Vitet]; 2 pages in-12. After the siege of Paris, and the publication of his Distractions, he sends a supplement which "contains a summary of my work on the reason for the necessity of a complex food for the diet of man and higher animals"; then he addresses "the question of materialism and spiritualism with respect to the physical-chemical sciences. Finally the distractions are ended by some facts and anecdotes of the Siege of Paris". He then praises M. Aveline who writes the minutes of the sessions of the Advisory Committee of Arts and Manufactures that he chairs; the committee "recruited in the Academy of Sciences, the Council of State, the Corps of Bridges and Roads and Mines, and finally the high industry and commerce, gives rise to the exemplary discussion of elements so varied, that it is necessary, in my opinion, an aptitude of well distinguished administrative spirit to summarize the discussion"...