J. B. Dumas took part in the discussion opened by Sainte Claire Deville, and agreed with his suggestions. He might have said more, however, on a subject which he often took up in private: the utility of pure science in daily experience. With his own special gift of generalization, he could have expounded the progress of all kinds due to the workers who, by their perseverance in resolving difficult problems, have brought about so many precious and unexpected results. Few men in France realized at that time that laboratories could be the vestibule of farms, factories, etc.; it was indeed a noble task, that of proving that science was intended to lighten the burden of humanity, not merely to be applied to devastation, carnage, and hatred. Pasteur was in the midst of these philosophical reflections when he received the following answer from the principal of the Faculty of Medicine of Bonn: “Sir, the undersigned, now Principal of the Faculty of Medicine of Bonn, is requested to answer the insult which you have dared to offer to the German nation in the sacred person of its august Emperor, King Wilhelm of Prussia, by sending you the expression of its _entire contempt_.”--DR. MAURICE NAUMANN. “P.S.--Desiring to keep its papers _free from taint_, the Faculty herewith returns your screed.” Pasteur’s reply contained the following: “I have the honour of informing you, Mr. Principal, that there are times when the expression of contempt in a Prussian mouth is equivalent for a true Frenchman to that of _Virum clarissimum_ which you once publicly conferred upon me.” After invoking in favour of Alsace-Lorraine, Truth, of Justice, and the laws of humanity, Pasteur added in a postscript-- “And now, Mr. Principal, after reading over both your letter and mine, I sorrow in my heart to think that men who like yourself and myself have spent a lifetime in the pursuit of truth and progress, should address each other in such a fashion, founded on my part on such actions. This is but one of the results of the character your Emperor has given to this war. You speak to me of _taint_. Mr. Principal, taint will rest, you may be assured, until far-distant ages, on the memory of those who began the bombardment of Paris when capitulation by famine was inevitable, and who continued this act of savagery after it had become evident to all men that it would not advance by one hour the surrender of the heroic city.” Whilst Pasteur thus felt those simple and strong impressions as a soldier or the man in the street might do, the creative power of his nature was urging him to great and useful achievements. He wrote from Lyons in March to M. Duclaux--