FIG. 2. PHOTOGRAPH OF CHEVREUL, taken on his one hundredth birthday. 

 He was asked to write in an album and replied : ' ' Que voulez vous : que j'ecrive 

 sur votre album ? Je vais e'crire mon premier principe philosophique, ce n'est 

 par moi, qui 1'ai formule, c'est Malebranche ' On doit tendre avec effort a 

 1'infallibilite, sans y pretendre.' " Chevreul was born Aug. 31, 1786, and died 

 Aug. 9, 1889. For the privilege of using this portrait I am indebted to Dr. 

 Henry P, Bowditch, to whom the interesting original belongs. 



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