Regnault’s father, the celebrated physicist, a member of the Institute, was at Geneva when he received this terrible blow. Another grief--not however comparable to the despair of a bereaved parent--befell him--an instance of the odious side of war, not in its horrors, its pools of blood and burnt dwellings, but in its premeditated cruelty. Regnault had left his laboratory utensils in his rooms at the Sèvres porcelain manufactory, of which he was the manager. Everything was apparently left in the same place, not a window was broken, no locks forced; but a Prussian, evidently an expert, had been there. “Nothing seemed changed,” writes J. B. Dumas, “in that abode of science, and yet everything was destroyed; the glass tubes of barometers, thermometers, etc., were broken; scales and other similar instruments had been carefully knocked out of shape with a hammer.” In a corner was a heap of ashes; they were the registers, notes, manuscripts, all Regnault’s work of the last ten years. “Such cruelty,” exclaimed J. B. Dumas, “is unexampled in history. The Roman soldier who butchered Archimedes in the heat of the onslaught may be excused--he did not know him; but with what sacrilegious meanness could such a work of destruction as this be accomplished!!!” On the very day when the Académie des Sciences was condoling with Henri Regnault’s sorrowing father, Pasteur, anxious at having had no news of his son, who had been fighting before Héricourt, determined to go and look for him in the ranks of the Eastern Army Corps. By Poligny and Lons-le-Saulnier, the roads were full of stragglers from the various regiments left several days behind, their route completely lost, who begged for bread as they marched, barely covered by the tattered remnants of their uniforms. The main body of the army was on the way to Besançon, a sad procession of French soldiers, hanging their heads under the cold grey sky and tramping painfully in the snow. Bourbaki, the general-in-chief, a hero of African battlefields, was becoming more and more unnerved by the combinations of this war. Whilst the Minister, in a dispatch from Bordeaux, had ordered him to move back towards Dôle, to prevent the taking of Dijon, then to hurry to Nevers or Joigny, where 20,000 men would be ready to be incorporated, Bourbaki, overwhelmed by the lamentable spectacle under his eyes, could see no resource for his corps but a last line of retreat, Pontarlier.